Elderly caretakers with Schizoaffective daughter

Hi everyone. I have a family eldery friend 80s-90s whose daughter 40s has Schizoaffective. She has no self control and has issues with anger. She hasn't attacked her parents before but she has bouts of rage where she has destroyed property. She has been in and out of psychiatric wards, they seem to have been short term stays than long term stays.

Im just worried about her parents as they're really old and are unfit to really care for her. As they get older, things will get worse as she is already taking meds. They are SF residents btw.

I was wondering what people who had friends or family members in similar circumstances have done in SF or the bay area.