My sister had my father sign bank signature card making her joint ownership of his bank account at AFFCU. We found out AFFCU was originally in my father's name but on the bank statement in Dec 2013 it shows her name as joint owner on his account. She did this illegally knowingly when several doctors have stated he has dementia and is unable to take care of himself and his finances. The doctor’s reports also indicated a statement from my sister that states she was aware of dementia for several years due to my father’s living habits and inability to care for himself. Now she refuses to take herself off the bank accounts. Adult Protective Services have been notified. My mom is his DPOA however it appears that she has been convinced by my sister that she hasn't done anything wrong.
Since your father is unable to care for himself due to his dementia, he is not competent. Accordingly, what your sister did is attempt to make an incompetent person make a gift to her. It is wrong. If she won't voluntarily fix, and probably anyway, you need to apply to be appointed guardian to take over your Dad's financial affairs to care for him. Consult with a probate attorney who does guardianships.
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If the agent under the DPOA refuses to take action to protect the principal then you may have to sue her as well. You can file an application to be appointed the Guardian of the Person and Estate of your father. You will have to hire a lawyer.
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Hire a lawyer and file to become your dad's guardian.
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