Help with down payment for grandchildren

I was on drugs and alcohol for 40 years. I have gotten myself clean through hard work and perseverance. During that time I lost my oldest child to a car accident and didn't have a very good relationship with my other 2 daughters. Now things are being repaired between us. I now have a chance to be in their lives and my 5 grandchildren lives. I need help with a down payment on a house so that I can stay in Pittsburgh and not be an absentee grand parent. That is something that I don't want because I see how my children and nieces and nephew treat my mother. She was an absent grandparent by her choice and they don't want to have a relationship with her. My children and my grandchildren are my world and I would do anything to stay in their lives. I know that I brought these problems on myself through years of neglect but I'm looking for a second chance. I can't do it in another state but if I don't come up with this money I'll be forced to move because I'll be homeless. If there is any way that there can be any help I'll appreciate immensely.