diff --git a/examples/create_synth_dlis.py b/examples/create_synth_dlis.py
index d12c3f91..42844122 100644
--- a/examples/create_synth_dlis.py
+++ b/examples/create_synth_dlis.py
@@ -3,7 +3,7 @@
 import logging
 
 from dlis_writer.writer.file import DLISFile
-from dlis_writer.logical_record.eflr_types import Origin
+from dlis_writer.logical_record.eflr_types.origin import OriginObject
 from dlis_writer.utils.logging import install_logger
 from dlis_writer.utils.enums import RepresentationCode
 
@@ -14,7 +14,8 @@
 
 
 # set up origin & file header with custom parameters - by creating an instance or dict of kwargs
-origin = Origin.make_object("DEFAULT ORIGIN", file_set_number=1, company="XXX")
+origin = OriginObject("DEFAULT ORIGIN", file_set_number=1, company="XXX")
+origin.creation_time.value = datetime(year=2023, month=12, day=6, hour=12, minute=30, second=5)
 file_header = {'sequence_number': 2}
 
 
diff --git a/src/dlis_writer/logical_record/core/eflr/eflr.py b/src/dlis_writer/logical_record/core/eflr/eflr.py
index cf46e1d4..39dfab46 100644
--- a/src/dlis_writer/logical_record/core/eflr/eflr.py
+++ b/src/dlis_writer/logical_record/core/eflr/eflr.py
@@ -112,6 +112,20 @@ def _make_body_bytes(self) -> bytes:
 
         return bts
 
+    def register_child(self, child: EFLRObject):
+        """Register a child EFLRObject with this EFLR."""
+
+        if not isinstance(child, self.object_type):
+            raise TypeError(f"Expected an instance of {self.object_type}; got {type(child)}: {child}")
+
+        self._object_dict[child.name] = child
+
+        if len(self._object_dict) == 1:
+            for attr_name, attr in child.attributes.items():
+                self._attributes[attr_name] = attr.copy()
+
+        child.origin_reference = self.origin_reference
+
     def make_object_in_this_set(self, name: str, get_if_exists: bool = False, **kwargs) -> EFLRObject:
         """Make an EFLRObject according the specifications and register it with this EFLR instance.
 
@@ -126,14 +140,9 @@ def make_object_in_this_set(self, name: str, get_if_exists: bool = False, **kwar
         if get_if_exists and name in self._object_dict:
             return self._object_dict[name]
 
-        obj = self.object_type(name, self, **kwargs)
-        self._object_dict[name] = obj
-
-        if len(self._object_dict) == 1:
-            for attr_name, attr in obj.attributes.items():
-                self._attributes[attr_name] = attr.copy()
+        obj = self.object_type(name, parent=self, **kwargs)
 
-        obj.origin_reference = self.origin_reference
+        self.register_child(obj)
 
         return obj
 
diff --git a/src/dlis_writer/logical_record/core/eflr/eflr_meta.py b/src/dlis_writer/logical_record/core/eflr/eflr_meta.py
index 2b204afe..0eaad26d 100644
--- a/src/dlis_writer/logical_record/core/eflr/eflr_meta.py
+++ b/src/dlis_writer/logical_record/core/eflr/eflr_meta.py
@@ -5,7 +5,6 @@
 from typing_extensions import Self
 
 from dlis_writer.logical_record.core.logical_record import LRMeta
-from dlis_writer.logical_record.core.eflr.eflr_object import EFLRObject
 
 if TYPE_CHECKING:
     from dlis_writer.logical_record.core.eflr.eflr import EFLR
diff --git a/src/dlis_writer/logical_record/core/eflr/eflr_object.py b/src/dlis_writer/logical_record/core/eflr/eflr_object.py
index cecc34ce..001be809 100644
--- a/src/dlis_writer/logical_record/core/eflr/eflr_object.py
+++ b/src/dlis_writer/logical_record/core/eflr/eflr_object.py
@@ -1,6 +1,6 @@
 import logging
 from functools import cached_property
-from typing import TYPE_CHECKING, Any, Union
+from typing import TYPE_CHECKING, Any, Union, Optional
 
 from dlis_writer.utils.struct_writer import write_struct_obname
 from dlis_writer.logical_record.core.attribute.attribute import Attribute
@@ -15,12 +15,15 @@
 class EFLRObject:
     """Model an object belonging to an Explicitly Formatted Logical Record - e.g. a particular channel."""
 
-    def __init__(self, name: str, parent: "EFLR", **kwargs):
+    parent_eflr_class: type["EFLR"] = NotImplemented
+
+    def __init__(self, name: str, parent: Optional["EFLR"] = None, set_name: Optional[str] = None, **kwargs):
         """Initialise an EFLRObject.
 
         Args:
             name        :   Name of the object. This will be the name it is stored with in the created DLIS file.
-            parent      :   EFLR instance this object belongs to.
+            parent      :   EFLR instance this object belongs to. If not provided, retrieved/made based on set_name.
+            set_name    :   Set name of the parent EFLR instance.
             **kwargs    :   Values to be set in attributes of this object.
 
         Note:
@@ -30,14 +33,40 @@ def __init__(self, name: str, parent: "EFLR", **kwargs):
 
         """
 
-        self.name = name                #: name of the object
-        self.parent = parent            #: EFLR instance this object belongs to
+        self.name = name    #: name of the object
+        self.parent = self._get_parent(parent=parent, set_name=set_name)  #: EFLR instance this object belongs to
+        self.parent.register_child(self)
 
         self.origin_reference: Union[int, None] = None    #: origin reference value, common for records sharing origin
         self.copy_number = 0            #: copy number of the object
 
         self.set_attributes(**{k: v for k, v in kwargs.items() if v is not None})
 
+    @classmethod
+    def _get_parent(cls, parent: Optional["EFLR"] = None, set_name: Optional[str] = None) -> "EFLR":
+        """Validate, retrieve, or create a parent EFLR instance.
+
+        Args:
+            parent      :   Parent EFLR instance. If not provided, set_name will be used to retrieve/make one.
+            set_name    :   Set name of the parent EFLR instance. If parent is provided, it is checked against its
+                            set_name.
+
+        Returns:
+            The parent EFLR instance.
+        """
+
+        if parent is not None:
+            if not isinstance(parent, cls.parent_eflr_class):
+                raise TypeError(f"Expected an instance of {cls.parent_eflr_class.__name__}; "
+                                f"got a {type(parent)}: {parent}")
+            if parent.set_name != set_name and set_name is not None:
+                raise ValueError(f"The provided set name: {set_name} does not match the set name of the "
+                                 f"provided parent EFLR: {parent.set_name}")
+
+            return parent
+
+        return cls.parent_eflr_class.get_or_make_eflr(set_name=set_name)
+
     @property
     def attributes(self) -> dict[str, Attribute]:
         """Attributes defined for this EFLRObject (sub)class with its values for the current instance."""
diff --git a/src/dlis_writer/logical_record/eflr_types/axis.py b/src/dlis_writer/logical_record/eflr_types/axis.py
index 8bfcf18c..27c5ad8e 100644
--- a/src/dlis_writer/logical_record/eflr_types/axis.py
+++ b/src/dlis_writer/logical_record/eflr_types/axis.py
@@ -8,12 +8,11 @@ class AxisObject(EFLRObject):
 
     parent: "Axis"
 
-    def __init__(self, name: str, parent: "Axis", **kwargs):
+    def __init__(self, name: str, **kwargs):
         """Initialise AxisObject.
 
         Args:
             name        :   Name of the AxisObject.
-            parent      :   Axis EFLR instance this AxisObject belongs to.
             **kwargs    :   Values of to be set as characteristics of the AxisObject Attributes.
         """
 
@@ -22,7 +21,7 @@ def __init__(self, name: str, parent: "Axis", **kwargs):
                                      converter=self.convert_maybe_numeric)
         self.spacing = NumericAttribute('spacing', parent_eflr=self)
 
-        super().__init__(name, parent, **kwargs)
+        super().__init__(name, **kwargs)
 
 
 class Axis(EFLR):
@@ -32,3 +31,5 @@ class Axis(EFLR):
     logical_record_type = EFLRType.AXIS
     object_type = AxisObject
 
+
+AxisObject.parent_eflr_class = Axis
diff --git a/src/dlis_writer/logical_record/eflr_types/calibration.py b/src/dlis_writer/logical_record/eflr_types/calibration.py
index d41e804e..b6dcfae1 100644
--- a/src/dlis_writer/logical_record/eflr_types/calibration.py
+++ b/src/dlis_writer/logical_record/eflr_types/calibration.py
@@ -16,12 +16,11 @@ class CalibrationMeasurementObject(EFLRObject):
 
     parent: "CalibrationMeasurement"
 
-    def __init__(self, name: str, parent: "CalibrationMeasurement", **kwargs):
+    def __init__(self, name: str, **kwargs):
         """Initialise CalibrationMeasurementObject.
 
         Args:
             name        :   Name of the CalibrationMeasurementObject.
-            parent      :   CalibrationMeasurement EFLR instance this CalibrationMeasurementObject belongs to.
             **kwargs    :   Values of to be set as characteristics of the CalibrationMeasurementObject Attributes.
         """
 
@@ -42,7 +41,7 @@ def __init__(self, name: str, parent: "CalibrationMeasurement", **kwargs):
         self.plus_tolerance = NumericAttribute('plus_tolerance', multivalued=True, parent_eflr=self)
         self.minus_tolerance = NumericAttribute('minus_tolerance', multivalued=True, parent_eflr=self)
 
-        super().__init__(name, parent, **kwargs)
+        super().__init__(name, **kwargs)
 
 
 class CalibrationMeasurement(EFLR):
@@ -58,12 +57,11 @@ class CalibrationCoefficientObject(EFLRObject):
 
     parent: "CalibrationCoefficient"
 
-    def __init__(self, name: str, parent: "CalibrationCoefficient", **kwargs):
+    def __init__(self, name: str, **kwargs):
         """Initialise CalibrationCoefficientObject.
 
         Args:
             name        :   Name of the CalibrationCoefficientObject.
-            parent      :   CalibrationCoefficient EFLR instance this CalibrationCoefficientObject belongs to.
             **kwargs    :   Values of to be set as characteristics of the CalibrationCoefficientObject Attributes.
         """
 
@@ -73,7 +71,7 @@ def __init__(self, name: str, parent: "CalibrationCoefficient", **kwargs):
         self.plus_tolerances = NumericAttribute('plus_tolerances', multivalued=True, parent_eflr=self)
         self.minus_tolerances = NumericAttribute('minus_tolerances', multivalued=True, parent_eflr=self)
 
-        super().__init__(name, parent, **kwargs)
+        super().__init__(name, **kwargs)
 
 
 class CalibrationCoefficient(EFLR):
@@ -89,12 +87,11 @@ class CalibrationObject(EFLRObject):
 
     parent: "Calibration"
 
-    def __init__(self, name: str, parent: "Calibration", **kwargs):
+    def __init__(self, name: str, **kwargs):
         """Initialise CalibrationObject.
 
         Args:
             name        :   Name of the CalibrationObject.
-            parent      :   Calibration EFLR instance this CalibrationObject belongs to.
             **kwargs    :   Values of to be set as characteristics of the CalibrationObject Attributes.
         """
 
@@ -109,7 +106,7 @@ def __init__(self, name: str, parent: "Calibration", **kwargs):
         self.parameters = EFLRAttribute('parameters', object_class=Parameter, multivalued=True, parent_eflr=self)
         self.method = Attribute('method', representation_code=RepC.IDENT, parent_eflr=self)
 
-        super().__init__(name, parent, **kwargs)
+        super().__init__(name, **kwargs)
 
 
 class Calibration(EFLR):
@@ -118,3 +115,8 @@ class Calibration(EFLR):
     set_type = 'CALIBRATION'
     logical_record_type = EFLRType.STATIC
     object_type = CalibrationObject
+
+
+CalibrationMeasurementObject.parent_eflr_class = CalibrationMeasurement
+CalibrationCoefficientObject.parent_eflr_class = CalibrationCoefficient
+CalibrationObject.parent_eflr_class = Calibration
diff --git a/src/dlis_writer/logical_record/eflr_types/channel.py b/src/dlis_writer/logical_record/eflr_types/channel.py
index 9f314005..e2ca9bd2 100644
--- a/src/dlis_writer/logical_record/eflr_types/channel.py
+++ b/src/dlis_writer/logical_record/eflr_types/channel.py
@@ -19,12 +19,11 @@ class ChannelObject(EFLRObject):
 
     parent: "Channel"
 
-    def __init__(self, name, parent: "Channel", dataset_name: Optional[str] = None, **kwargs):
+    def __init__(self, name, dataset_name: Optional[str] = None, **kwargs):
         """Initialise ChannelObject.
 
         Args:
             name            :   Name of the ChannelObject.
-            parent          :   Channel EFLR instance this ChannelObject belongs to.
             dataset_name    :   Name of the data corresponding to this channel in the SourceDataObject.
             **kwargs        :   Values of to be set as characteristics of the ChannelObject Attributes.
         """
@@ -47,7 +46,7 @@ def __init__(self, name, parent: "Channel", dataset_name: Optional[str] = None,
 
         self._dataset_name: Union[str, None] = dataset_name
 
-        super().__init__(name, parent, **kwargs)
+        super().__init__(name, **kwargs)
 
         self.set_defaults()
 
@@ -157,3 +156,6 @@ class Channel(EFLR):
     set_type = 'CHANNEL'
     logical_record_type = EFLRType.CHANNL
     object_type = ChannelObject
+
+
+ChannelObject.parent_eflr_class = Channel
diff --git a/src/dlis_writer/logical_record/eflr_types/computation.py b/src/dlis_writer/logical_record/eflr_types/computation.py
index e4303a20..a0f12fb9 100644
--- a/src/dlis_writer/logical_record/eflr_types/computation.py
+++ b/src/dlis_writer/logical_record/eflr_types/computation.py
@@ -15,12 +15,11 @@ class ComputationObject(EFLRObject):
 
     parent: "Computation"
 
-    def __init__(self, name: str, parent: "Computation", **kwargs):
+    def __init__(self, name: str, **kwargs):
         """Initialise ComputationObject.
 
         Args:
             name            :   Name of the ComputationObject.
-            parent          :   Computation EFLR instance this ComputationObject belongs to.
             **kwargs        :   Values of to be set as characteristics of the ComputationObject Attributes.
         """
 
@@ -32,7 +31,7 @@ def __init__(self, name: str, parent: "Computation", **kwargs):
         self.values = NumericAttribute('values', multivalued=True, parent_eflr=self)
         self.source = EFLRAttribute('source', parent_eflr=self)
 
-        super().__init__(name, parent, **kwargs)
+        super().__init__(name, **kwargs)
 
         self._set_defaults()
         self.check_values_and_zones()
@@ -58,3 +57,6 @@ class Computation(EFLR):
     set_type = 'COMPUTATION'
     logical_record_type = EFLRType.STATIC
     object_type = ComputationObject
+
+
+ComputationObject.parent_eflr_class = Computation
diff --git a/src/dlis_writer/logical_record/eflr_types/equipment.py b/src/dlis_writer/logical_record/eflr_types/equipment.py
index 04453f95..e692a1b8 100644
--- a/src/dlis_writer/logical_record/eflr_types/equipment.py
+++ b/src/dlis_writer/logical_record/eflr_types/equipment.py
@@ -8,12 +8,11 @@ class EquipmentObject(EFLRObject):
 
     parent: "Equipment"
 
-    def __init__(self, name: str, parent: "Equipment", **kwargs):
+    def __init__(self, name: str, **kwargs):
         """Initialise EquipmentObject.
 
         Args:
             name        :   Name of the EquipmentObject.
-            parent      :   Equipment EFLR instance this EquipmentObject belongs to.
             **kwargs    :   Values of to be set as characteristics of the EquipmentObject Attributes.
         """
 
@@ -35,7 +34,7 @@ def __init__(self, name: str, parent: "Equipment", **kwargs):
         self.radial_drift = NumericAttribute('radial_drift', parent_eflr=self)
         self.angular_drift = NumericAttribute('angular_drift', parent_eflr=self)
 
-        super().__init__(name, parent, **kwargs)
+        super().__init__(name, **kwargs)
 
 
 class Equipment(EFLR):
@@ -45,3 +44,5 @@ class Equipment(EFLR):
     logical_record_type = EFLRType.STATIC
     object_type = EquipmentObject
 
+
+EquipmentObject.parent_eflr_class = Equipment
diff --git a/src/dlis_writer/logical_record/eflr_types/file_header.py b/src/dlis_writer/logical_record/eflr_types/file_header.py
index 9d3e9b77..6f751a12 100644
--- a/src/dlis_writer/logical_record/eflr_types/file_header.py
+++ b/src/dlis_writer/logical_record/eflr_types/file_header.py
@@ -16,12 +16,11 @@ class FileHeaderObject(EFLRObject):
 
     identifier_length_limit = 65    #: max length of the file header name
 
-    def __init__(self, identifier: str, parent: "FileHeader", sequence_number: int = 1, **kwargs):
+    def __init__(self, identifier: str, sequence_number: int = 1, **kwargs):
         """Initialise FileHeaderObject.
 
         Args:
             identifier      :   Name of the FileHeaderObject.
-            parent          :   FileHeader EFLR instance this FileHeaderObject belongs to.
             sequence_number :   Sequence number of the file.
             **kwargs        :   Values of to be set as characteristics of the FileHeaderObject Attributes.
         """
@@ -34,7 +33,7 @@ def __init__(self, identifier: str, parent: "FileHeader", sequence_number: int =
         if len(identifier) > self.identifier_length_limit:
             raise ValueError(f"'identifier' length should not exceed {self.identifier_length_limit} characters")
 
-        super().__init__(name='0', parent=parent, **kwargs)
+        super().__init__(name='0', **kwargs)
 
     def _make_attrs_bytes(self) -> bytes:
         """Create bytes describing the values of attributes of FIleHeaderObject."""
@@ -73,3 +72,5 @@ def _make_template_bytes(self) -> bytes:
 
         return bts
 
+
+FileHeaderObject.parent_eflr_class = FileHeader
diff --git a/src/dlis_writer/logical_record/eflr_types/frame.py b/src/dlis_writer/logical_record/eflr_types/frame.py
index b4a7c446..9be9d2b4 100644
--- a/src/dlis_writer/logical_record/eflr_types/frame.py
+++ b/src/dlis_writer/logical_record/eflr_types/frame.py
@@ -26,12 +26,11 @@ class FrameObject(EFLRObject):
         'VERTICAL-DEPTH'
     )
 
-    def __init__(self, name: str, parent: "Frame", **kwargs):
+    def __init__(self, name: str, **kwargs):
         """Initialise FrameObject.
 
         Args:
             name        :   Name of the FrameObject.
-            parent      :   Frame EFLR instance this FrameObject belongs to.
             **kwargs    :   Values of to be set as characteristics of the FrameObject Attributes.
         """
 
@@ -46,7 +45,7 @@ def __init__(self, name: str, parent: "Frame", **kwargs):
         self.index_min = NumericAttribute('index_min', parent_eflr=self)
         self.index_max = NumericAttribute('index_max', parent_eflr=self)
 
-        super().__init__(name, parent, **kwargs)
+        super().__init__(name, **kwargs)
 
     @classmethod
     def parse_index_type(cls, value: str) -> str:
@@ -136,3 +135,6 @@ class Frame(EFLR):
     set_type = 'FRAME'
     logical_record_type = EFLRType.FRAME
     object_type = FrameObject
+
+
+FrameObject.parent_eflr_class = Frame
diff --git a/src/dlis_writer/logical_record/eflr_types/group.py b/src/dlis_writer/logical_record/eflr_types/group.py
index fd9a313c..ed95d53e 100644
--- a/src/dlis_writer/logical_record/eflr_types/group.py
+++ b/src/dlis_writer/logical_record/eflr_types/group.py
@@ -13,7 +13,7 @@ class GroupObject(EFLRObject):
 
     parent: "Group"
 
-    def __init__(self, name: str, parent: "Group", **kwargs):
+    def __init__(self, name: str, **kwargs):
         """Initialise GroupObject.
 
         Args:
@@ -27,7 +27,7 @@ def __init__(self, name: str, parent: "Group", **kwargs):
         self.object_list = EFLRAttribute('object_list', multivalued=True, parent_eflr=self)
         self.group_list = EFLRAttribute('group_list', object_class=Group, multivalued=True, parent_eflr=self)
 
-        super().__init__(name, parent, **kwargs)
+        super().__init__(name, **kwargs)
 
 
 class Group(EFLR):
@@ -36,3 +36,6 @@ class Group(EFLR):
     set_type = 'GROUP'
     logical_record_type = EFLRType.STATIC
     object_type = GroupObject
+
+
+GroupObject.parent_eflr_class = Group
diff --git a/src/dlis_writer/logical_record/eflr_types/long_name.py b/src/dlis_writer/logical_record/eflr_types/long_name.py
index 25b3ad25..b91a54b3 100644
--- a/src/dlis_writer/logical_record/eflr_types/long_name.py
+++ b/src/dlis_writer/logical_record/eflr_types/long_name.py
@@ -8,12 +8,11 @@ class LongNameObject(EFLRObject):
 
     parent: "LongName"
 
-    def __init__(self, name: str, parent: "LongName", **kwargs):
+    def __init__(self, name: str, **kwargs):
         """Initialise LongNameObject.
 
         Args:
             name        :   Name of the LongNameObject.
-            parent      :   LongName EFLR instance this LongNameObject belongs to.
             **kwargs    :   Values of to be set as characteristics of the LongNameObject Attributes.
         """
 
@@ -37,7 +36,7 @@ def __init__(self, name: str, parent: "LongName", **kwargs):
         self.standard_symbol = Attribute('standard_symbol', representation_code=RepC.ASCII, parent_eflr=self)
         self.private_symbol = Attribute('private_symbol', representation_code=RepC.ASCII, parent_eflr=self)
 
-        super().__init__(name, parent, **kwargs)
+        super().__init__(name, **kwargs)
 
 
 class LongName(EFLR):
@@ -46,3 +45,6 @@ class LongName(EFLR):
     set_type = 'LONG-NAME'
     logical_record_type = EFLRType.LNAME
     object_type = LongNameObject
+
+
+LongNameObject.parent_eflr_class = LongName
diff --git a/src/dlis_writer/logical_record/eflr_types/message.py b/src/dlis_writer/logical_record/eflr_types/message.py
index 2ddd4536..2496428e 100644
--- a/src/dlis_writer/logical_record/eflr_types/message.py
+++ b/src/dlis_writer/logical_record/eflr_types/message.py
@@ -8,12 +8,11 @@ class MessageObject(EFLRObject):
 
     parent: "Message"
 
-    def __init__(self, name: str, parent: "Message", **kwargs):
+    def __init__(self, name: str, **kwargs):
         """Initialise MessageObject.
 
         Args:
             name        :   Name of the MessageObject.
-            parent      :   Message EFLR instance this MessageObject belongs to.
             **kwargs    :   Values of to be set as characteristics of the MessageObject Attributes.
         """
 
@@ -25,7 +24,7 @@ def __init__(self, name: str, parent: "Message", **kwargs):
         self.angular_drift = NumericAttribute('angular_drift', parent_eflr=self)
         self.text = Attribute('text', representation_code=RepC.ASCII, multivalued=True, parent_eflr=self)
 
-        super().__init__(name, parent, **kwargs)
+        super().__init__(name, **kwargs)
 
 
 class Message(EFLR):
@@ -41,18 +40,17 @@ class CommentObject(EFLRObject):
 
     parent: "Comment"
 
-    def __init__(self, name: str, parent: "Comment", **kwargs):
+    def __init__(self, name: str, **kwargs):
         """Initialise CommentObject.
 
         Args:
             name        :   Name of the CommentObject.
-            parent      :   Comment EFLR instance this CommentObject belongs to.
             **kwargs    :   Values of to be set as characteristics of the CommentObject Attributes.
         """
 
         self.text = Attribute('text', representation_code=RepC.ASCII, multivalued=True, parent_eflr=self)
 
-        super().__init__(name, parent, **kwargs)
+        super().__init__(name, **kwargs)
 
 
 class Comment(EFLR):
@@ -61,3 +59,7 @@ class Comment(EFLR):
     set_type = 'COMMENT'
     logical_record_type = EFLRType.SCRIPT
     object_type = CommentObject
+
+
+MessageObject.parent_eflr_class = Message
+CommentObject.parent_eflr_class = Comment
diff --git a/src/dlis_writer/logical_record/eflr_types/no_format.py b/src/dlis_writer/logical_record/eflr_types/no_format.py
index 9c15d2e4..2d3a0281 100644
--- a/src/dlis_writer/logical_record/eflr_types/no_format.py
+++ b/src/dlis_writer/logical_record/eflr_types/no_format.py
@@ -8,19 +8,18 @@ class NoFormatObject(EFLRObject):
 
     parent: "NoFormat"
 
-    def __init__(self, name: str, parent: "NoFormat", **kwargs):
+    def __init__(self, name: str, **kwargs):
         """Initialise NoFormatObject.
 
         Args:
             name        :   Name of the NoFormatObject.
-            parent      :   NoFormat EFLR instance this NoFormatObject belongs to.
             **kwargs    :   Values of to be set as characteristics of the NoFormatObject Attributes.
         """
 
         self.consumer_name = Attribute('consumer_name', representation_code=RepC.IDENT, parent_eflr=self)
         self.description = Attribute('description', representation_code=RepC.ASCII, parent_eflr=self)
 
-        super().__init__(name, parent, **kwargs)
+        super().__init__(name, **kwargs)
 
 
 class NoFormat(EFLR):
@@ -29,3 +28,6 @@ class NoFormat(EFLR):
     set_type = 'NO-FORMAT'
     logical_record_type = EFLRType.UDI
     object_type = NoFormatObject
+
+
+NoFormatObject.parent_eflr_class = NoFormat
diff --git a/src/dlis_writer/logical_record/eflr_types/origin.py b/src/dlis_writer/logical_record/eflr_types/origin.py
index 6094bef7..8170dafd 100644
--- a/src/dlis_writer/logical_record/eflr_types/origin.py
+++ b/src/dlis_writer/logical_record/eflr_types/origin.py
@@ -14,12 +14,11 @@ class OriginObject(EFLRObject):
 
     parent: "Origin"
 
-    def __init__(self, name: str, parent: "Origin", **kwargs):
+    def __init__(self, name: str, **kwargs):
         """Initialise OriginObject.
 
         Args:
             name        :   Name of the OriginObject.
-            parent      :   Origin EFLR instance this OriginObject belongs to.
             **kwargs    :   Values of to be set as characteristics of the OriginObject Attributes.
         """
 
@@ -49,7 +48,7 @@ def __init__(self, name: str, parent: "Origin", **kwargs):
             logger.info("Creation time ('creation_time') not specified; setting it to the current date and time")
             kwargs["creation_time"] = datetime.now()
 
-        super().__init__(name, parent, **kwargs)
+        super().__init__(name, **kwargs)
 
 
 class Origin(EFLR):
@@ -58,3 +57,6 @@ class Origin(EFLR):
     set_type = 'ORIGIN'
     logical_record_type = EFLRType.OLR
     object_type = OriginObject
+
+
+OriginObject.parent_eflr_class = Origin
diff --git a/src/dlis_writer/logical_record/eflr_types/parameter.py b/src/dlis_writer/logical_record/eflr_types/parameter.py
index 27ca9bbe..43948205 100644
--- a/src/dlis_writer/logical_record/eflr_types/parameter.py
+++ b/src/dlis_writer/logical_record/eflr_types/parameter.py
@@ -15,12 +15,11 @@ class ParameterObject(EFLRObject):
 
     parent: "Parameter"
     
-    def __init__(self, name: str, parent: "Parameter", **kwargs):
+    def __init__(self, name: str, **kwargs):
         """Initialise ParameterObject.
 
         Args:
             name        :   Name of the ParameterObject.
-            parent      :   Parameter EFLR instance this ParameterObject belongs to.
             **kwargs    :   Values of to be set as characteristics of the ParameterObject Attributes.
         """
 
@@ -30,7 +29,7 @@ def __init__(self, name: str, parent: "Parameter", **kwargs):
         self.zones = EFLRAttribute('zones', object_class=Zone, multivalued=True, parent_eflr=self)
         self.values = Attribute('values', converter=self.convert_maybe_numeric, multivalued=True, parent_eflr=self)
 
-        super().__init__(name, parent, **kwargs)
+        super().__init__(name, **kwargs)
 
         self._set_defaults()
 
@@ -49,3 +48,5 @@ class Parameter(EFLR):
     logical_record_type = EFLRType.STATIC
     object_type = ParameterObject
 
+
+ParameterObject.parent_eflr_class = Parameter
diff --git a/src/dlis_writer/logical_record/eflr_types/path.py b/src/dlis_writer/logical_record/eflr_types/path.py
index 99d756ad..4e546520 100644
--- a/src/dlis_writer/logical_record/eflr_types/path.py
+++ b/src/dlis_writer/logical_record/eflr_types/path.py
@@ -16,12 +16,11 @@ class PathObject(EFLRObject):
 
     parent: "Path"
 
-    def __init__(self, name: str, parent: "Path", **kwargs):
+    def __init__(self, name: str, **kwargs):
         """Initialise PathObject.
 
         Args:
             name        :   Name of the PathObject.
-            parent      :   Path EFLR instance this PathObject belongs to.
             **kwargs    :   Values of to be set as characteristics of the PathObject Attributes.
         """
 
@@ -38,7 +37,7 @@ def __init__(self, name: str, parent: "Path", **kwargs):
         self.measure_point_offset = NumericAttribute('measure_point_offset', parent_eflr=self)
         self.tool_zero_offset = NumericAttribute('tool_zero_offset', parent_eflr=self)
 
-        super().__init__(name, parent, **kwargs)
+        super().__init__(name, **kwargs)
 
 
 class Path(EFLR):
@@ -47,3 +46,6 @@ class Path(EFLR):
     set_type = 'PATH'
     logical_record_type = EFLRType.FRAME
     object_type = PathObject
+
+
+PathObject.parent_eflr_class = Path
diff --git a/src/dlis_writer/logical_record/eflr_types/process.py b/src/dlis_writer/logical_record/eflr_types/process.py
index a9003f41..8b6a40d4 100644
--- a/src/dlis_writer/logical_record/eflr_types/process.py
+++ b/src/dlis_writer/logical_record/eflr_types/process.py
@@ -18,12 +18,11 @@ class ProcessObject(EFLRObject):
 
     allowed_status = ('COMPLETE', 'ABORTED', 'IN-PROGRESS')  #: allowed values of the 'status' Attribute
 
-    def __init__(self, name: str, parent: "Process", **kwargs):
+    def __init__(self, name: str, **kwargs):
         """Initialise ProcessObject.
 
         Args:
             name        :   Name of the ProcessObject.
-            parent      :   Process EFLR instance this ProcessObject belongs to.
             **kwargs    :   Values of to be set as characteristics of the ProcessObject Attributes.
         """
 
@@ -43,7 +42,7 @@ def __init__(self, name: str, parent: "Process", **kwargs):
         self.parameters = EFLRAttribute('parameters', object_class=Parameter, multivalued=True, parent_eflr=self)
         self.comments = Attribute('comments', representation_code=RepC.ASCII, multivalued=True, parent_eflr=self)
 
-        super().__init__(name, parent, **kwargs)
+        super().__init__(name, **kwargs)
 
     @classmethod
     def check_status(cls, status):
@@ -58,3 +57,6 @@ class Process(EFLR):
     set_type = 'PROCESS'
     logical_record_type = EFLRType.STATIC
     object_type = ProcessObject
+
+
+ProcessObject.parent_eflr_class = Process
diff --git a/src/dlis_writer/logical_record/eflr_types/splice.py b/src/dlis_writer/logical_record/eflr_types/splice.py
index 5b06d048..90dca82f 100644
--- a/src/dlis_writer/logical_record/eflr_types/splice.py
+++ b/src/dlis_writer/logical_record/eflr_types/splice.py
@@ -15,12 +15,11 @@ class SpliceObject(EFLRObject):
 
     parent: "Splice"
 
-    def __init__(self, name: str, parent: "Splice", **kwargs):
+    def __init__(self, name: str, **kwargs):
         """Initialise SpliceObject.
 
         Args:
             name        :   Name of the SpliceObject.
-            parent      :   Splice EFLR instance this SpliceObject belongs to.
             **kwargs    :   Values of to be set as characteristics of the SpliceObject Attributes.
         """
 
@@ -28,7 +27,7 @@ def __init__(self, name: str, parent: "Splice", **kwargs):
         self.input_channels = EFLRAttribute('input_channels', object_class=Channel, multivalued=True, parent_eflr=self)
         self.zones = EFLRAttribute('zones', object_class=Zone, multivalued=True, parent_eflr=self)
 
-        super().__init__(name, parent, **kwargs)
+        super().__init__(name, **kwargs)
 
 
 class Splice(EFLR):
@@ -37,3 +36,6 @@ class Splice(EFLR):
     set_type = 'SPLICE'
     logical_record_type = EFLRType.STATIC
     object_type = SpliceObject
+
+
+SpliceObject.parent_eflr_class = Splice
diff --git a/src/dlis_writer/logical_record/eflr_types/tool.py b/src/dlis_writer/logical_record/eflr_types/tool.py
index c18e1fc7..01ffb123 100644
--- a/src/dlis_writer/logical_record/eflr_types/tool.py
+++ b/src/dlis_writer/logical_record/eflr_types/tool.py
@@ -16,12 +16,11 @@ class ToolObject(EFLRObject):
 
     parent: "Tool"
 
-    def __init__(self, name: str, parent: "Tool", **kwargs):
+    def __init__(self, name: str, **kwargs):
         """Initialise ToolObject.
 
         Args:
             name        :   Name of the ToolObject.
-            parent      :   Tool EFLR instance this ToolObject belongs to.
             **kwargs    :   Values of to be set as characteristics of the ToolObject Attributes.
         """
 
@@ -33,7 +32,7 @@ def __init__(self, name: str, parent: "Tool", **kwargs):
         self.channels = EFLRAttribute('channels', object_class=Channel, multivalued=True, parent_eflr=self)
         self.parameters = EFLRAttribute('parameters', object_class=Parameter, multivalued=True, parent_eflr=self)
 
-        super().__init__(name, parent, **kwargs)
+        super().__init__(name, **kwargs)
 
 
 class Tool(EFLR):
@@ -42,3 +41,6 @@ class Tool(EFLR):
     set_type = 'TOOL'
     logical_record_type = EFLRType.STATIC
     object_type = ToolObject
+
+
+ToolObject.parent_eflr_class = Tool
diff --git a/src/dlis_writer/logical_record/eflr_types/well_reference_point.py b/src/dlis_writer/logical_record/eflr_types/well_reference_point.py
index 2115b872..45587ead 100644
--- a/src/dlis_writer/logical_record/eflr_types/well_reference_point.py
+++ b/src/dlis_writer/logical_record/eflr_types/well_reference_point.py
@@ -8,12 +8,11 @@ class WellReferencePointObject(EFLRObject):
 
     parent: "WellReferencePoint"
 
-    def __init__(self, name: str, parent: "WellReferencePoint", **kwargs):
+    def __init__(self, name: str, **kwargs):
         """Initialise WellReferencePointObject.
 
         Args:
             name        :   Name of the WellReferencePointObject.
-            parent      :   WellReferencePoint EFLR instance this WellReferencePointObject belongs to.
             **kwargs    :   Values of to be set as characteristics of the WellReferencePointObject Attributes.
         """
 
@@ -40,7 +39,7 @@ def __init__(self, name: str, parent: "WellReferencePoint", **kwargs):
         self.coordinate_3_value = NumericAttribute(
             'coordinate_3_value', representation_code=RepC.FDOUBL, parent_eflr=self)
 
-        super().__init__(name, parent, **kwargs)
+        super().__init__(name, **kwargs)
 
 
 class WellReferencePoint(EFLR):
@@ -49,3 +48,6 @@ class WellReferencePoint(EFLR):
     set_type = 'WELL-REFERENCE'
     logical_record_type = EFLRType.OLR
     object_type = WellReferencePointObject
+
+
+WellReferencePointObject.parent_eflr_class = WellReferencePoint
diff --git a/src/dlis_writer/logical_record/eflr_types/zone.py b/src/dlis_writer/logical_record/eflr_types/zone.py
index 710fc55f..3b7e327f 100644
--- a/src/dlis_writer/logical_record/eflr_types/zone.py
+++ b/src/dlis_writer/logical_record/eflr_types/zone.py
@@ -1,5 +1,3 @@
-from datetime import datetime
-
 from dlis_writer.logical_record.core.eflr import EFLR, EFLRObject
 from dlis_writer.utils.enums import EFLRType, RepresentationCode as RepC
 from dlis_writer.logical_record.core.attribute import Attribute, DTimeAttribute
@@ -12,12 +10,11 @@ class ZoneObject(EFLRObject):
 
     domains = ('BOREHOLE-DEPTH', 'TIME', 'VERTICAL-DEPTH')  #: allowed values for 'domain' Attribute
 
-    def __init__(self, name: str, parent: "Zone", **kwargs):
+    def __init__(self, name: str, **kwargs):
         """Initialise ZoneObject.
 
         Args:
             name        :   Name of the ZoneObject.
-            parent      :   Zone EFLR instance this ZoneObject belongs to.
             **kwargs    :   Values of to be set as characteristics of the ZoneObject Attributes.
         """
 
@@ -26,14 +23,7 @@ def __init__(self, name: str, parent: "Zone", **kwargs):
         self.maximum = DTimeAttribute('maximum', allow_float=True, parent_eflr=self)
         self.minimum = DTimeAttribute('minimum', allow_float=True, parent_eflr=self)
 
-        super().__init__(name, parent, **kwargs)
-
-        if self.domain.value == 'TIME':
-            if not all(isinstance(v, (datetime, type(None))) for v in (self.minimum.value, self.minimum.value)):
-                raise TypeError("Zone maximum and minimum should be instances of datetime.datetime")
-        else:
-            if not all(isinstance(v, ((int, float), type(None))) for v in (self.minimum.value, self.minimum.value)):
-                raise TypeError("Zone maximum and minimum should be numbers")
+        super().__init__(name, **kwargs)
 
     @classmethod
     def check_domain(cls, domain: str) -> str:
@@ -50,3 +40,6 @@ class Zone(EFLR):
     set_type = 'ZONE'
     logical_record_type = EFLRType.STATIC
     object_type = ZoneObject
+
+
+ZoneObject.parent_eflr_class = Zone