Mom gets upset and tells her caregivers that one or all of her siblings or grandkids have been killed, or they've been beat up. I wonder if this is similar to how a faulty memory can cause a PWD to believe people who passed away long ago are still alive. Is this delusion as common? She has it all the time, but she never thinks her parents are still living. I wonder if it's the same type of process in the brain.
If dreams just talk to her, try to get her to know that it was a dream. (difficult for a person with dementia) But validate the fear and then redirect. "Wow mom, that was a scary dream, why don't we go get some tea and talk a bit."
If she indeed has had a sibling or grandchild that has been killed or hurt in any way this is her brain processing what is there. (sort of like the Summer Reruns we have on TV now)
If this is a hallucination talk to her doctor about the hallucinations and there are medications that can help.
There is so little rhyme or reason why dementia patients do the things they do.
I would tell the aids , to not make a big deal outta it when she says this. Maybe an I'm sorry and change the subject. An im sorry, because in her heart she believes it at that moment. And change the subject so she doesn't dwell on it.
Best of luck
We were really careful about what she saw on tv, what movies she watched, what she read. Basically we only allowed her to what certain animated movies that had very little "stressful" or distressing content. Even some kid's movies were too much for her. So she never watched the news or any other shows on tv -- even some commercials set her off.
So, I would suggested controlling what media and content she is exposed to going forward. Once we got it under control, my Aunt was better, but not completely free of dark and negative thougthts (since is the part of the brain that is "left" after the ravages of dementia).