POA for Mother taken by brother

What is the name of your state?What is the name of your state? New York

My question is complicated and twisted in that my father recently passed away and my mother has dementia (Dad was her caregiver for the last several years) and my brother was POA for Dad and I was POA for my Mom. My brother has a mental illness called Bipolar Disorder and he has to be in "Control" and my sister and I questioned his behavior as POA for Dad since he was taking money from their accounts to pay his bills, etc. Well, after Dad passed away he couldn't stand not being in control, so he took our Mother to a different attorney other than her own and had her change her POA from me to my brother and another brother (who are both in financial troubles). My mother does not understand what she did. Is this legal? And my brother has made statements about me to several individuals that I verbally abused my mother which is false!!!!! Do I have any legal recourse here. Sorry, several things going on all at once. My brother took my mother to his home in NJ the day after changing POA and my mother fell in his home and broke her hip. Now I am afraid that he will keep her in NJ and I will not be able to see her. He is making it impossible for me to have contact with her. It sounds so suspicious to me that she falls and breaks her hip the day after he takes her to a lawyer behind my back. Can you help me???? Thank you--I am desperate.

We must be living parallel lives - the exact same thing happened to me when my mother died. I was DPA and my sister coerced my father to sign a revocation 4 days after my mother's funeral. What ended up happening to your mother?