What became of Jeff's Mother? His income?

I watched this last night on P.O.V. What a really strange film. Although, at one point Jeff's daughter goes to visit his father at a nursing home in New York, but I don't think it was ever said what became of his mother. She was talked about, but I don't remember him saying what happened to her. I assume she died, but how?

Also, where was Jeff getting his money from? They never showed him having a job. I thought he might be receiving SSI/disability money (he did appear to be 'mental' and eccentric enough to qualify for public disability), but for whatever reason this was never said.

I can, also, understand how one of the daughters reaction was that she didn't want to visit him out in California because of his conspiracy theories, and they appeared to be alike from his emails, fearing she would end up like him living in a RV out in a parking lot. I've always had fears of ending up homeless and forced to live that way as well. Even though Jeff seemed happy, his life seemed frightening to me.

"I'm Chickie! Fly Me to Quaalude!"