re: Advice on Gramdparent/Parent/Child relationship

Had the same situation with my dad and his very large extended family. I knocked him out when I was 19 after things came to a head and hadn't talked to him for years after. When my 2nd child was born, I tried to patch things. Like you, it didn't take long before I realized he was the same douche. Instead of flat cutting him off, I gave him the opportunity to change. I talked to him man to man and explained I didn't want my children to see of fraction of the man of knew as kid and if he could not change than the ramifications were on him, not me. Talk to your folks, explain the situation and make it abundantly clear - they f up and they're done.