I have a house & estate that I am making a will for. I want to be able to leave what I have to an Aunt &. She inherited another house before that they have spent time refurbishing. There was some dispute in the family over the inheritence of that house between her & her 2 twins who feel they should have gotten the house. My Aunt said before that if she ever came into money she would let them have the house (or at least let them live in it which would mean they wouldn't be getting the Rent they would otherwise get). I want her to get the full benefit of it, if she gets my house but loses her other house to the twins she won't be benefitting from it like she could be. Can you put a stipulation into a will where she would get my estate if she sold her other house so that it would stop her sisters from coming in to anything?