Legal Question in Civil Rights Law in Louisiana

I believe this was asked before. But regardless, if you have a valid power-of-attorney you should have recorded it in every Parish where there is property and the Parish where your father lives, and a copy given to all the banks and creditors so that they know to do business only with you. If you did all that, then your sister cannot do anything with the banks or anyone else because if they deal with her, then they are liable for any harm done. But I suspect you do not even have a legally binding written power-of-attorney or this would not be happening.