How can I get my husband to stop giving away money?

My husband is in the beginning stages of dementia. He has 3 grown daughters from a previous marriage and 3 grandkids. He is forever trying to give them as well as a nephew money. His favorite phrase is "all you have to do is ask" and sometimes they do. I am 20 yrs younger than my husband and work about 50 hrs a week at my job and he draws a very, very modest retirement. His family never asks what is going on with his health. They just laugh it off as forgetfulness. I don't want to take his name off of our accounts because he is capable of going to the grocery or hardware store and I don't want to treat him like a child, but I have had it with the handouts.