diff --git a/app/routers/api_crud_v3_nested.py b/app/routers/api_crud_v3_nested.py
index d8f6673..b76a248 100644
--- a/app/routers/api_crud_v3_nested.py
+++ b/app/routers/api_crud_v3_nested.py
@@ -1,4 +1,5 @@
-from fastapi import APIRouter, Depends, Path, Query, Request, Response
+from fastapi import APIRouter, Depends, Path, Query, Request, Response, Header
+from pydantic import ValidationError
 from typing import Optional, Union
 import asyncio
 import logging
@@ -132,6 +133,7 @@ async def post_child_obj(
         parent_obj_id: str = Path(min_length=11, max_length=22),
         child_obj_type: str = Path(min_length=2, max_length=50),
         return_obj: Optional[bool] = True,
+        x_ae_ignore_extra_fields: Optional[bool] = Header(False),
         account: AccountContext = Depends(get_account_context),
         serialization: SerializationParams = Depends(),
         delay: DelayParams = Depends(),
@@ -170,22 +172,28 @@ async def post_child_obj(
     input_model = obj_cfg.get('mdl_in', obj_cfg.get('mdl'))
     output_model = obj_cfg.get('mdl_out', obj_cfg.get('mdl_default', obj_cfg.get('mdl')))
 
+    if not table_name_insert or not input_model or not table_name_select or not output_model:
+        return mk_resp(data=False, status_code=500, response=response, status_message=f"Configuration error.")
+
     if not account.super and account.auth_method != 'bypass' and account.account_id:
         if 'account_id' in input_model.__fields__:
             obj_data['account_id'] = account.account_id
 
     obj_data[f'{parent_obj_type}_id'] = resolved_parent_id
 
+    # Sanitize payload (ID resolution, virtual fields, and optionally extra fields)
+    sanitize_payload(obj_data, input_model, ignore_extra=x_ae_ignore_extra_fields)
+
     try:
         validated_obj = input_model(**obj_data)
+    except ValidationError as e:
+        structured_errors = {err['loc'][-1]: err['msg'] for err in e.errors()}
+        return mk_resp(data=False, status_code=400, response=response, status_message="Validation Failed", details=structured_errors)
     except Exception as e:
         return mk_resp(data=False, status_code=400, response=response, status_message="Validation Failed", details=str(e))
 
     data_to_insert = validated_obj.dict(exclude_unset=True)
 
-    # Sanitize payload (remove virtual fields and view-only fields)
-    sanitize_payload(data_to_insert, input_model)
-
     if sql_insert_result := sql_insert(data=data_to_insert, table_name=table_name_insert):
         new_obj_id = sql_insert_result
         new_obj_id_random = get_id_random(record_id=new_obj_id, table_name=child_obj_type)
@@ -248,6 +256,7 @@ async def patch_child_obj(
         child_obj_type: str = Path(min_length=2, max_length=50),
         child_obj_id: str = Path(min_length=11, max_length=22),
         return_obj: Optional[bool] = True,
+        x_ae_ignore_extra_fields: Optional[bool] = Header(False),
         account: AccountContext = Depends(get_account_context),
         serialization: SerializationParams = Depends(),
         delay: DelayParams = Depends(),
@@ -271,6 +280,7 @@ async def patch_child_obj(
     obj_cfg = obj_type_kv_li[child_obj_type]
     table_name_update = obj_cfg.get('tbl_update', obj_cfg.get('tbl'))
     table_name_select = obj_cfg.get('tbl_default', obj_cfg.get('tbl'))
+    input_model = obj_cfg.get('mdl_in', obj_cfg.get('mdl'))
     output_model = obj_cfg.get('mdl_out', obj_cfg.get('mdl_default', obj_cfg.get('mdl')))
 
     if existing_child := sql_select(table_name=table_name_select, record_id=resolved_child_id):
@@ -279,8 +289,8 @@ async def patch_child_obj(
     else:
         return mk_resp(data=False, status_code=404, response=response, status_message="Child not found.")
 
-    # Sanitize payload (remove virtual fields and view-only fields)
-    sanitize_payload(obj_data, output_model)
+    # Sanitize payload (ID resolution, virtual fields, and optionally extra fields)
+    sanitize_payload(obj_data, input_model, ignore_extra=x_ae_ignore_extra_fields)
 
     if sql_update(data=obj_data, table_name=table_name_update, record_id=resolved_child_id):
         if return_obj: