Index: relativity.module
===================================================================
--- relativity.module	(revision 125)
+++ relativity.module	(working copy)
@@ -1001,7 +1001,7 @@
         $parents = explode(',', $node->parent_node);
         foreach($parents as $parent_nid) {
           $parent = node_load($parent_nid);
-          if (!$parent || !in_array($parent->type, variable_get('relativity_type_'. $node->type, array()))) {
+          if (!$parent || !in_array($node->type, variable_get('relativity_type_'. $parent->type, array()))) {
             form_set_error('relativity_type'.$node->type, t('You\'re not allowed to create this type of attachment.'));
           }
         }