Sounds like Beth is trying to take control of Mom's property and finances, and Mom's not going for it. Beth emails brother to back up her bullshit claims.
Well, Beth took control of Mom's property and finances several years ago, so now she has no finances, and the camper is the extent of her remaining property.
The brother briefly crammed himself into the camper, along with Beth, her Mom, and Beth's two big smelly dogs.
They all lived there together for a short while.
Poor, stupid Beth hated it, and described her brother's unfortunate mental illness to her DUmpmates.
Everyone around poor, stupid Beth is mentally ill. Mom is nuts, Doug was a crazy drug addict, her brother was nuts.
Poor, stupid Beth, in addition to being the stupidest person on all the internets, is of course nuts.
Apparently the only sane people in poor, stupid Beth's entire extended family are her sons, happily residing in facilities provided by the California Department of Corrections.