<human>: Give me a shortened version of the text

Recently my granddad passed away, he left all his money and assets to my grandma. Now for some pre-text, my grandma has early Alzheimers so recently has become really forgetful and is deteriorating mentally but not to the point where she needs to be in care.

Her brother is a horrible man and also younger who never bothered about her when she needed help and never visited her or tried to contact her (despite living about a 10 minute drive away). Now because she has money he is visiting her every day. Since he has started visiting her money has gone missing and bank books. She has also been into her bank with him and over the past week withdrew a large amount of money. He is being really rude to my father and uncle (his brother) who have really lost patience with the situation.

Is there any way we can legally stop him taking advantage of my grandma, a vulnerable elderly woman?     

We have had advice that my father and uncle should gain control of her assets legally but for that she needs to be deemed mentally unfit or declare herself unfit but as it stands she isn't in the full onset of Alzheimers and wont accept that soon she will be unable to take care of herself.
<bot>: Grandma's brother is taking advantage of her to gain money and we cant stop it because she thinks she's stable even though she isn't.