My mom left to Mexico last year, I am sponsoring her to become a legal resident in the U.S. She has two minor children whom she left in the care of her sister in Texas. The aunt has the Power of Attorney over the children but recently moved to AZ. Now, she wants to move to CA and leave the children with my brother & I. It has been decided the children will live with my brother due the fact that he has more room to spare. Do we have to get another Power of Attorney from my mom, can my aunt's Power of Attorney be somehow transferred to us or does my mom have to revoke the Power of Attorney she gave my aunt and sign a new one assigning it to us or to my brother since the children will be living with him? Please help!