Can a person named in a Will of a deceased request from the person that had been power of attorney for the past year a record all monies spent?

I had been power of attorney of my father. I live in a different state than he does. My sister, who resides in the state of my father, got him to change the power of attorney over to her. He is now deceased. Two months prior to his death, she was also able to convince him to leave his house to her and the remaining assets for us to split. I had been executor of his estate and in October it was changed to her. She refuses to return any calls to me. My sister has not spoken to me in 25 years and spend the majority of her adult life not speaking to my parents, though she lives 3 miles away from them. A year ago my mother became ill and then passed. My sister has 7 adult children. My sister\'\'s children helped my sister care for my parents. Throughout their lives, they manipulated my parents into giving them everything they wanted. My mother passed in 2011 and my father 2 months ago. During that time, her adult children were still manipulating him to do as they wanted.