So, trying to make a long story concise. I had 3 chickens I raised and they were an ideal little backyard flock. They jostled a little for position but all 3 got along and roosted close and seemed to be attached to each other. Then one had to go and die on me. The remaining 2 seemed off, and when one would go to lay the other seemed lost. I impulsively accepted an adolescent (12 week old) cochin hen and tried to integrate her slowly using exercise pens to have her range next to the older girls and by making a sectioned off area in the coop. I was surprised how aggressive one of my girls seemed to her, but I knew this could be normal. Well, then the cochin escaped her coop enclosure very early one morning, and when we went to let them out we found her crumpled up with her head pecked open to the skull. Very traumatic. So I was able to get her healed, its amazing, and I ended up with another chick because she had to be separated for several weeks while she healed. I was able to get a mini coop from a friend who was getting rid of it and the 4 girls have co existed side by side, then gradually could free range together, then are able to be in my sizable chicken yard together. Big meanie still charges at them but seems satisfied when they defer or move away. I got a better bigger coop, with 8' of roost space attached to a 4x8 foot run. I moved the two babies (who are adult size now) and the less aggressive of the original two into the new coop, with no issues so far. Mean girl is sleeping in the mini coop. I was hoping that giving them the new coop it would not be her territory to defend, and that she could be integrated so all 4 would sleep in the new coop at night. My husband is dead set against it, and feels the dominant hen cannot be trusted and would end up attacking the young girls at some point. I would really like to have 1 coop to clean and get eggs from and just keep the mini coop for a hospital coop or eventually when we end up with new babies. Is he right? Is it reasonable to expect that they could sleep in the same place? or should I just assume I will have to keep them separated forever?