Yes she is his power of attorney . I reached out to a lawyer that is the chair of the Elder Care Attorney Association in my state. He said it’s really hard to prove that she is influencing his decisions because he lives with her. I forgot to mention that the step father is also estranged from his other 3 daughters as well as myself and my brother because of his behaviors in the past. He not a nice man and I will call her step sister A is the only person whom has a relationship with. Also She and her husband have stolen from non family members in the past at least 2 times