If that is how the girls feel about their mother, then perhaps staying with you and your mom for Easter would be a good idea. I would not push them on their mother or try and tell them what their feeling are or aren't. Don't take sides against or for her, just stay neutral. Let the kids decide how they feel.
It is not about what you feel should work in your M. It is about doing the work that gets the right results. Do what works!
