I have a group of pullets that are almost 16 weeks old. I added 4 pullets that I was told were the same age (drove 2 hours to get them). When we got there it was obvious they were younger. I could not leave them there. They were all picking on each other and all the chickens were missing their tail feathers. I quarantined for well over a week. My existing chickens would not let them out of the coop even after 2 full weeks together. I did not like nor will I tolerate the fussing and arguing they were doing. DH built me a second coop inside the run and fenced off some of the run. He even took 2 days of his vacation time to finish it up. New coop is 4x6 and 5 ft tall. He raised it 2 foot off the ground so they have as much ground space as possible. Only 4 chickens will be in this one. The fenced area for them is 6.5x 10.5. (I wish it could be more.) They moved in yesterday and so far EVERYONE is much more relaxed. I will try and get my son to help me figure out the picture posting part and add pics later today. I have now got: 2 BA 3 EE 2 California white 1 GLW 1 Splash Hamburg 1 BO I got a lot of the design ideas from BYC. Thanks to everyone for all the great information! Front of the main coop (former shed) with the diagonal door allowing for some storage and more airflow. The new small coop for 4 chickens. With the door open. Side of small coop and human door. The new smaller hens. Ducky (splash Hamburg), Peaches (BO), Apple (EE), and Lacey (GLW) A few of the bigger girls. Thank You all again for all the great information.