4.7.1

I've got a bit of a process problem that is stumping me.. On the DocumentNew event I am creating a child node for a certain document type.  Something like If alias=="Person" create a child "Credentials".  Ok that works fine, easy enough but now when I copy a Person, it copies the Person and its credentials and creates a second credentials node.

I've tried to cancel that event in various places but can't seem to get it down.. This seems like a simple thing but is stumping me.. Can someone recommend how to go about cancelling the DocumentNew for that child type when the parent node is copied?