Legal Question in Wills and Trusts in Pennsylvania

No. However, is the power of attorney recorded, like at the recorder of deeds' office? If so, its a public record and anyone can see it. Otherwise, there is no law mandating that it be shared with you.

Are your parents still mentally competent? Do you feel that your sister is abusing the power of attorney in some way? If your parents are competent then they can revoke the power of attorney at any time if they suspect abuse or misfeasance. If they are not competent then you can always bring a guardianship proceeding. You will have to prove at the proceeding that your parents are not competent. You will also have to persuade the court that they should appoint you as the guardian of the person and/or property. The guardian of the person makes healthcare decisions; the guardian of the property make financial decisions and handle financial and property transactions. I suggest that you get a lawyer to maximize your chances for success in such case.