I don't normally reach out to strangers but I'm hoping I can get some unbiased guidance. I am a mom to two beautiful girls, almost 6 and 20 months. My 6 year old is with a previous relationship and my youngest is from my current marriage. We have a loving marriage and our youngest is a happy sweet little girl. My oldest is a very bright beautiful little girl but she struggles with authority. I blame her father and his lack of proper parenting in his home. He doesn't have rules, she's allowed to talk to him how ever she wants, and has even exhibited aggressive behavior towards him. He does nothing about it. When she comes to my house I try to keep it fun and light hearted but it usually ends up with me having to correct her or send her to her room. She has been physically mean to my youngest and is mean to our pets. I'm at a loss. I'm considering giving her father primary physical custody. I would still have shared legal custody of her but she would be in his home more than mine. I'm trying to do what's right for everyone involved but I'm not sure what is exactly right I guess. Any positive or helpful thoughts would be great, especially from someone that's gone through something similar or knows a similar situation. Thanks.