I started out with seven 6 month old hens (Easter Eggers, Wyandottes, buff) and just added three 3 month old easter eggers to our flock. We quarantined, and then kept them in a dog kennel in the coop at night, and a fenced off area in the day in the run for about two weeks. Then I set up a fence outside the coop, added the three new ones to it, and added a chicken per hour and watched. With minimal pecking, and no blood or sores or feathers out, we had success. After they all hung out in the "new run" for a couple hours we put them back in the coop together. This worked for us and now they are all doing well together. Good luck!
Edited by Alagrace - 9/22/15 at 8:56pm