:Yorkietal
Welcome to our large and growing YorkieTalk family, Michael. How wonderful it was of you to rescue those two little ones in need. All of the fur members of your family need time to adjust. The Boxers are still pups and the Yorkies came from who knows what kind of environment.
Take it slow and let the Yorkie girls settle in. Several members of this forum have (or had) Boxers with their yorkies. Sadly, we lost our 15 year old Boxer last summer. Boo was the best baby sitter and loved her Yorkie siblings.
Good luck and please post pics of both your Yorkie girls and the Boxers when you have time.