I had medical and financial POA for my parents, which they established years ago. About 1-1/2 years ago, my sister took it upon herself to make her the POA for medical naming my brother second and her husband 3rd. My mother has Alzheimer's and would not have been able to make this decision wisely. She also had a friend witness the signing and another friend notarize. I do not think my father's signature on the document is his. How can I get this changed back to me?
The only way of getting the Power of Attorney back into your name is for your parents to make an appointment with an Attorney and express their wishes to have you as their Power of Attorney. Since your Mom has Alzheimer's and cannot make this decision then this cannot be done. What about your Dad? How is his health? Could he still understand a legal document? If yes, he can change his own POA and name you as his POA.
Was the medical POA designated as part of the advance care directive document? Were there other changes to the document?
Do you and your sister disagree about medical care for mother? Does one of you want her in a care center and the other thinks she can stay at home? Does one of you strongly object to DNR orders, and the other believes in them? Is this more about your father's medical care than your mother's? Does one want cremation and the other a full-scale traditional funeral?
What I'm getting at is why is it so important who has medical POA? Would there be significant differences in the outcome to your parents depending on who has it?
My mother never designated a medical POA at all. If any of the 7 of her children had been able to talk her into filling out an advance medical director, the other 6 of us would have been relieved. I don't think anyone would have cared who was named medical POA. It would just be good to know that someone could make decisions for Mom.
So I am interested in why this is so important to you. (NOT saying it shouldn't be. Just wanting to understand the background.)
I doubt you could prove that Mom didn't have capacity to understand the document 18 months ago. You might be able to prove Dad's signature was forged. But if Dad wants Sister as his medical POA, all he would have to do is have a new document made with a valid signature. And if he wants you, the same is true -- just make a new document. There really is no value in proving the signature is forged.
People with dementia can sign medical POA documents, as long as they can demonstrate they understand what it means. My husband said, "It means that if I'm too sick to make decisions, Jeanne can decide for me." Are you sure that your mother couldn't do this now?