Noted lots of checks written on moms account that my mom did not write. I believe they have taken thousands over the years. My lying brother said he never took a penny. I believe he has bought items for his home and saying receipts for mom. They are wolves in sheep clothing. Wife is a huge lier and everytime she opens her mouth another lie comes out. She is constantly trying to justify her stealing. My mom is afraid of them. Unfortunately I live in another state. She does everything herself except getting groceries which we have someone doing that now. What to do. Lawyer?
Who is the financial Power of Attorney? Who is the health Power of Attorney? If your brother is Power of Attorney, then yes he can write checks on your Mom's account for her care. If Mom lives in Assisted Living, that can cost $4k-$7k per month. If your Mom lives with your brother, age related expenses are not cheap.
As for your brother's wife writing checks for him on your Mom's account, how do you know that she hasn't signed a "signature card" at the bank allowing her to do same? Is it possible that your brother finds it difficult now to write checks?
If you go to an Attorney, saying "I believe" won't hold up. You need to have solid proof that money is being used not for your Mom. What proof do you have that your Mom is afraid of her son and his wife? If your Mom has dementia, sadly dementia can cause someone to make up stories.
If this isn't the case and your mom actually is impaired and vulnerable then you will need to take hard evidence to an attorney to assess whether you have a winnable case. If no one is her PoA, then guadianship may become an issue. If family fights over an elder then court may not like this and choose to assign a court-appointed independent guardian who is not family.
FYI a FoA is under no obligation to divulge anything to other famiily members. Your Mom's info is considered private and protected. If the only source of information is your Mom, please note that as cognitive decline and memory loss increases, clarity and accuracy of reality and events become fuzzier (been there done that with my several elderly LOs). In other words -- you will need to be absolutely sure (and have actual proof) of criminal activity before pursuing this further.
Just make sure that when your mother needs more caregiving (and she's what, 95 or so now?), that YOU don't have to be the one who takes her in if your brother has stolen money from her.
How much is in her estate? Are you depending on an inheritance?