diff --git a/apps/wpm/filters.py b/apps/wpm/filters.py
index bf8064f2..cb349e2f 100644
--- a/apps/wpm/filters.py
+++ b/apps/wpm/filters.py
@@ -186,6 +186,7 @@ class MlogbFilter(filters.FilterSet):
             "wm_in__state": ["exact"],
             "material_in": ["exact", "isnull"],
             "material_out": ["exact", "isnull"],
+            "parent": ["exact", "isnull"],
         }
     
     def filter_type(self, queryset, name, value):