Filtering the Page Parent dropdown

Hey folks!

Random question for any WordPress-whizzes out there… I’m currently working on a site which is going to have quite a lot of pages, and a bunch of different editors.

I’m trying to streamline the admin area as much as possible (as some of the editors aren’t entirely tech-savvy) and one item I’m stuck on at the moment is the Page/Post Parent dropdown menu on the page edit screen.

I’m already modified functions.php so that once an editor logs in they only see the pages they themselves have created. And I was wondering whether there’s any way to do something similar for the Page Parent dropdown? Whereby only pages that person had created appearing in the dropdown list?

Any suggestions or help would be great!

Thanks
Jon