Can I prevent elder financial abuse before it occurs?

[ManaPT]

Hello,

My cousin and her elderly Mom lived together, and a week ago my cousin died.  My cousin's bookkeeper has now convinced the elderly Mom to let her (the bookkeeper) move in and help her with everything, including paying the bills.  All this has happened within days of the death.  I suspect that the bookkeeper was embezzling from my cousin and now is making a play for her mom.  I don't have proof I just find her behavior disturbing.  She hasn't moved in yet.

My brother is executor of my cousin's will which will help in sorting things out somewhat.  What can I do?  The elderly Mom is very worried about living alone, and very happy that the bookkeeper wants to live with her.  She is mostly okay mentally, but very vulnerable right now and she does have a drinking problem and could be convinced to sign papers while impaired.  Thanks for your help!