The Wills are meaningless until your parents die. The Power of Attorney is the operative document. That said, because of your siblings actions, the only real recourse is a conservatorship/guardianship. You need to contact an Elder Law attorney ASAP to help you out and evaluate your best course of action.
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Attorney Shultz is correct. A will is revocable, changeable and not legally binding until after the person who signed it has died. Unfortunately in your circumstances, as Attorney Shultz noted, the person holding power of attorney has legal authority during your parents' lifetimes until there is a court appointment. Accordingly, your only real option is to go to court to attempt to be appointed as your parents' fiduciary. Good luck to you.
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