I think living near by is a valid option. How about retirement home? Small apartment? Hiring help for her? Taking another mortgage is unreasonable. She doesn’t need to be living with you but other arrangements could be made. Your husband feels he needs to do something. She is not just any kind of random “old woman”. Not like he wants to take care of a neighbor.

I don’t see any need to fight. It could be discussed kindly and some compromise could be reached. Sure his brother is a jerk but it doesn’t mean your husband should also wash his hands off and be just as horrid.

Sadly sometimes one sibling washes hands off elderly parents. The reality is usually the other one picks up a slack. What else could be done? If my brother decided to become a jerk, I’d not abandon my dad or become a jerk myself