Hello, I have two 11 week old pullets. I had a third, but she ended up being a he, so we exchanged him today. The chicken lady gave us a new 3-4 week old pullet. She said to keep them separate until the youngest was at least 75% the size of the others. I'm worried that the new pullet will be lonely if she's alone for so long, but we really can't handle more than 3 right now. I'm considering building a small tractor to put right next to the others house, so they can get used to each other. Do you think this will help? At what age can I start giving them supervised social time? Thanks!