What can I do for an elderly cousin who is being financially abused and possibly physically abused?

My cousin, who is like a sister to my Mom and like a 2nd Mom to me has been placed into a boarding home by her daughter. She is not allowed to have a cell phone. She has no idea about her finances. Her daughter says she is "crazy" (incompetent). However, she has passed a competency test "with flying colors" given by a physician. Her car was sold without her permission; her house was almost sold...until they discovered it was deeded to her until her death. I need to know what I can do as a mere cousin to prevent her daughter from doing this to her.