diff --git a/caldav/objects.py b/caldav/objects.py
index 46c9dfc..f0c65bd 100644
--- a/caldav/objects.py
+++ b/caldav/objects.py
@@ -170,7 +170,7 @@ def children(
             props=props, multi_value_props=multiprops
         )
 
-        for path in list(properties.keys()):
+        for path in properties:
             resource_types = properties[path][dav.ResourceType.tag]
             resource_name = properties[path][dav.DisplayName.tag]