My new chickens are not quite getting along with the old girls like I'd hoped they would. Pecking order has not been established and there is no peace. The older girls are picking on the new girls and the new girls are picking on the young girls. The new girls have taken up residence in the tree in the run (no problems there at all) and the coop (chasing the layers away from the nest boxes causing me to need to make additional boxes in the run). The new girls know where the coop is and spend much of the day in there, but they refuse to sleep in there. For the last week I've allowed them to sleep in the tree. Should I allow them to continue this or should I force integration and put them in the coop at night?