diff --git a/src/griffe/diff.py b/src/griffe/diff.py
index bcea8bac..293883b6 100644
--- a/src/griffe/diff.py
+++ b/src/griffe/diff.py
@@ -446,14 +446,14 @@ def _member_incompatibilities(
     seen_paths: set[str] | None = None,
 ) -> Iterator[Breakage]:
     seen_paths = set() if seen_paths is None else seen_paths
-    for name, old_member in old_obj.members.items():
+    for name, old_member in old_obj.all_members.items():
         if ignore_private and name.startswith("_"):
             logger.debug(f"API check: {old_obj.path}.{name}: skip private object")
             continue
 
         logger.debug(f"API check: {old_obj.path}.{name}")
         try:
-            new_member = new_obj.members[name]
+            new_member = new_obj.all_members[name]
         except KeyError:
             is_module = not old_member.is_alias and old_member.is_module
             if is_module or old_member.is_exported(explicitely=False):
diff --git a/tests/test_diff.py b/tests/test_diff.py
index eaeebecd..4d1f675f 100644
--- a/tests/test_diff.py
+++ b/tests/test_diff.py
@@ -185,3 +185,25 @@ def test_diff_griffe(old_code: str, new_code: str, expected_breakages: list[Brea
     assert len(breaking) == len(expected_breakages)
     for breakage, expected_kind in zip(breaking, expected_breakages):
         assert breakage.kind is expected_kind
+
+
+def test_moving_members_in_parent_classes() -> None:
+    """Test that moving an object from a base class to a parent class doesn't trigger a breakage."""
+    old_code = """
+        class Parent:
+            ...
+
+        class Base(Parent):
+            def method(self):
+                ...
+    """
+    new_code = """
+        class Parent:
+            def method(self):
+                ...
+
+        class Base(Parent):
+            ...
+    """
+    with temporary_visited_module(old_code) as old_package, temporary_visited_module(new_code) as new_package:
+        assert not list(find_breaking_changes(old_package, new_package))