If I share part of the tree with a family member with the ability to edit, what exactly can they edit or not edit?

Question

I'd like to share part of my tree to a cousin, however, I want him to be able to add/edit his parents and/or grandparents as he may have better information than I.  What are they limited to when sharing and allowing them to edit?

Answer 1

Two points:

1. You can't share "part" of a tree. The share function shares the whole tree.
2. Once you give edit permission to the tree to someone and they create their own account, they can do anything to the tree that you can (add, edit or delete stuff).

Be carefull to whom you give edit access and always keep a backup copy of you tree in case they muck it up.