I haven't gotten along very well with my father over the years but we always maintained our relationship. Now he is suffering from what I believe to be some form of dementia. His new girlfriend and I really don't get along and I believe, based on conversation I've had with my father, that the girlfriend is trying to get him to change his estate plan so that everything goes to her, even though my dad has always said he wanted to leave some assets to me, his only child. Two questions, is it possible to disinherit a child in Massachusetts legally. And if you can and he does because of undue influence by his girlfriend is it true that if I challenge the will that I will lose whatever he did leave to me in the will?