I have been with my boyfriend for about a year now. I have known him for almost 5 years. He was an amzing single dad and has done great taking care of his two girls on his own. We have hung out with the kids a few times when we first got together and I knew right away the youngest was going to be the issue. 

My sd's bm is an awful parent..  Doesn't believe in manners, brushing teeth or hair, cannot enforce any boundaries, doesn't care about schooling, let's her eat sweets all day..... It goes on... Its killing me as I love her like she's my own.... Any tips please