When you're old, you need to be treated like a baby - the schedule is VERY important.

Anger is definitely one of the awful sides of dementia - some patients also become quite violent and sex crazed

Unfortunately there are changes to the brain that cause the behavior changes. Tell your mom to remember that it's the disease process at work, and to not take what he says personally.

Changes to their environment are disorienting and tough on dementia patients, so it's best to try to minimize any disruptions. If her brother doesn't elicit the same hostile reaction, perhaps she can ask him to deal with their dad when it's necessary, and she can do more of what doesn't directly involve him, like bill paying.

Personality changes are very normal in dementia. Can his wife live there with him?

My mother is dealing with something similar, but my grandfather being a jerk isn't new. She tries not to visit alone and doesn't visit frequently.

My grandfather is 92, has been in great health but has a knee problem, is starting to show signs on dementia, can no longer drive and needs some minor help (someone to count pills etc). After a rough bout with a cold this past winter, he was hospitalized and went downhill cognitively. My mom and 2 uncles talked him into moving into an apartment in an assisted living home, where he has his own place but there's a cafeteria and social schedule and buses. He's pissed about it but knows it's necessary since there are things he can't do. He was living with second wife of 10 years, but because of his knee he can't get around their house anymore and she couldn't handle his care, so he agreed to move into the apartment.

Well, he's been there 2 months and it's going downhill. He is just so angry at my mom. He's paranoid, blames her for any issues he has, is suspicious of their oversight of his money (my mom and uncle are powers of attorney and managing for him). He calls her up screaming about the slightest things, then forgets they had a discussion and he agreed to it. For example, he had a bedroom at my uncle's house for a few years, but then moved in with his second wife. My uncle recently got rid of the furniture and took down a wall to do some remodeling. He told my grandfather about it, but grandfather forgot until he went by the visit. Somehow my mom gets the heat for all this. My grandfather is just so angry. Everything pisses him off.

Why do people get like this in old age? It's ripping my mom apart to have her dad hating her at the end of his life.