She is permitted to do that under the Power of Attorney, in that the account was 100% both of yours. At any time, you could have removed the money, just as your mother could have (or her agent). It does sound like there was some sneaky maneuvering on your sister's part, but it was entirely legal. As your mother's agent, she is responsible to show that she's acted in her mother's fiduciary interest. It may be worth it to speak to a lawyer about this. It's certainly possible that a court could order her to return the money to the joint account.
Answered on Jul 03rd, 2012 at 2:15 PM