stupid, greedy, selfish,
I'm no lawyer but I assume they're planning to say he wasn't in his right mind due to the Alzheimer's when he made the will.
Compare that to all the records showing that they didn't know he had Alzheimer's when they married (she didn't marry him for the house), that she was his full-time caretaker, etc. and she should win. But the emotional toll, not to mention legal fees, just isn't worth it.
If his children had had to hire someone to care for him 24/7, it would have cost them far more than your aunt is going to inherit. Make that "some people to care for him." You can't hire someone to work those kinds of hours. Your aunt did it for love.
I hope the daughter has to travel home so often that her career goes down the drain because she misses so much work. (And that she loses the case.)