diff -r 061796d9855e -r 507dd7bc8cb5 svghmi/hmi_tree.py
--- a/svghmi/hmi_tree.py	Tue Apr 06 11:47:07 2021 +0200
+++ b/svghmi/hmi_tree.py	Tue Apr 06 14:04:08 2021 +0200
@@ -125,7 +125,9 @@
         # hash is computed on demand
         node = cls(path, name, nodetype, hmiclass=hmiclass)
         for child in enode.iterchildren():
-            node.children.append(cls.from_etree(child))
+            newnode = cls.from_etree(child)
+            newnode.parent = weakref.ref(node)
+            node.children.append(newnode)
         return node
 
     def traverse(self):