Hi, I have 3 adult chickens and 3 (3-month old) chickens, one of which is a rooster. I've kept the younger ones in a temporary coop next to the bigger ones thus far. I let them all out to forage during the day, but they pretty much stay separate except when forced together; then, the leader of the older chickens shows her dominance. What is the best way to get them to become one flock? Both coops are too small to do the "playpen" method one inside of the other (bigger coop is 2-level, with the nest boxes and roost on top, and forage area underneath, but it's not very high underneath, and the door is too small to put much in there except chickens.) Thanks for any help!