I'm a 42 year old step mother to a 13year old girl who constantly causes me and my husband to argue like crazy. We've been together for 7 years. Married for 4years and we have a 3 year old daughter together. I've noticed my husband big time favors the 13 year old. And treats our 3 year old like crap. He yells and spanks my 3 year old for stupid reasons. And I don't like it at all. Never once has he yelled or spanked his 13 year old. But I feel that she deserves it. She back talks him and he allows it. She's not doing good in school because of the circle of friends that she chooses.