--- a/src/pyams_utils/include.py	Thu Jun 14 08:58:27 2018 +0200
+++ b/src/pyams_utils/include.py	Thu Jun 14 13:57:57 2018 +0200
@@ -22,6 +22,7 @@
 
 # import packages
 from chameleon import PageTemplateFile
+from pyams_utils.container import ParentSelector
 from pyams_utils.context import ContextSelector
 from pyams_utils.request import get_annotations, get_debug, RequestSelector
 from pyams_utils.site import site_factory
@@ -50,6 +51,7 @@
 
     # add custom subscriber predicate to filter events via supported interface(s)
     config.add_subscriber_predicate('context_selector', ContextSelector)
+    config.add_subscriber_predicate('parent_selector', ParentSelector)
     config.add_subscriber_predicate('request_selector', RequestSelector)
 
     # load registry components