Where do we begin to help an aging mother who is allowing her indigent, alcoholic 58-year-old son to live with her and paying his bills/living expenses?

I appreciate all of your help. Maybe a wellness check is in order!

The area agency on aging should be able to advise you how to get a wellness check in your area. It may be that if you can't reach her for a few days you can ask the police to check. But call the agency first, for their advice.

As others have said, if Mother has not been declared incompetent by a court, she is entitled to use her money any way she wants. I think your goal would be to determine that she is not being coerced but is making her decisions freely. Try not to antagonize your brother. He may be in the picture long term.

Visits in the home with the son/brother are needed. Not to criticize or make accusations but to observe the general condition of the living arrangements and the health of both. How old is the mother? She might wish for a confidant or moral support as she must feel very alone with the problem if her son is continuing to drink. If you could help him you would be helping her.
The area on aging seems the best course since the family seems hesitate to deal with the brother but of course you can't leave your mom in danger.
Does your mom have a dr you could check in with?
I'm glad you are looking into this. Don't give up.

You could call your local Area Agency on Aging and ask them how to get a "wellness check". This means an agency (probably APS) would arrive unannounced at her home and ask her about what her needs are.

Be aware that if she needs Medicaid to pay for a Nursing Home within 5 years, they are going to disqualify her based on her monetary gifts to her son.

Does your mother have any physical problems that require a caregiver? If she is mentally competent, there isn't much you can do besides try to intervene as a family. Many alcoholics find themselves in the situation your brother is in. They can lose jobs and wives in their addiction. There is really not much of a way to help them until they choose the change for themselves. Some never do. My older brother was one the alcoholics that never chose to change. He died at 57.

It is difficult for a mother to turn her back on a son even if it means she is enabling him. What would he do if your mother wasn't propping him up? I imagine that she has been doing it for much of his life. That's the way it tends to go with alcoholic sons.

Do you have any idea of how much your brother is drinking now? He won't tell you the truth most likely, but you can tell. If he is broke, it means he is using your mother's money to buy the alcohol. I hope he doesn't have expensive taste.

I don't know what to tell you. If she were incompetent you could call in APS to help. If she is competent, however, she has the ability to choose what she wants to do. Keep talking to her as a family and see if you can figure out any workable solutions for your brother. I hope everyone can visit frequently to try to get a feel for what is going on.

Until you get engaged you can't take any action. He maybe a functional alcholic who takes care of her and the value would be equal too more to pay someone else vs what's being distributed to him. Get engaged and find out details

Unfortunately, we do not live in the same city. We visit when we can, but meet her and the aunt away from the house. The intent of my original question was who is available (agencies, legal assistance, etc.) to even help direct us? Thank you.

Maybe you should take turns visiting her