I spent several weeks with my cochin chicks (10 weeks at the time) in a rabbit hutch in my bantam's chicken tractor (it's an 8x8 tractor). Then I did "visits" where they were allowed out in the yard. Then I did "open door hours" when I was working outside, with the hutch door open. Finally I moved to "open door, all the time" and after three days of pecking and chest bumping they finally settled down. The resulting flock order was kind of odd - the older two stayed together, the younger three stayed together and there was rarely any pecking. Unless the "hen" which turned out to be a rooster started strutting. Neither of the older hens would tolerate that (immediate peck, but no chasing). I essentially had a flock of two and a flock of three in the same run. Yesterday I moved the tractor and redid their nest and roost box. The chickens spent most of their time running in fear while I gradually moved the tractor. I finally moved my runt chicks (who are runts no longer) into the rabbit hutch. Oh, the pecking at the wires that ensued!. Still, I have to say that it worked. Last night they roosted together. Today the five of them are moving together and very little pecking. The rooster even "serviced" one of the older hens. (Poor rooster - this is an urban area and this will not end well). Putting them in a hutch where they could see (but not peck) for several weeks Visiting hours outside the coop or in a neutral area. Visiting hours with a place for the new ones to escape Open access with a place for the new ones to escape and finally a traumatic experience to make everyone have worse things to worry about than whether or not a new chicken is around. I'll repeat the process with the "baby" chicks (we still call them that, even though they are taller than the bantams). I'm pretty confident it will work. On a side note, when I put the little ones in the hutch, the others kept clucking as they walked around them. One of the chicks (a barred rock/cochin cross) turned its head and opened its mouth and made a sort of growling noise. It did it again. Then on the third try - a cluck! The other chick kept moving its head back and forth, staring at the one that had clucked like it was some sort of alien. The br/cochin proceeded to cluck to itself quietly as it walked about, eating. The little cochin continued to cheep and began to dash back and forth in the hutch. Then it approached its barred rock sister and they looked at each other. "Cluck cluck cluck," said the barred rock. "Cheep." "Cluck" "Cheep Cheep Cheep Cheep" and then - "Cluck". They spent the rest of the time I was outside clucking constantly. "Look what I can do! Cluck!" Today I haven't heard a cheep one. All clucks.In time the rooster will go where roosters go. The hens will stay and I'm sure that with the same steps I used with the first ones we'll have one nice flock. Thanks!