I had two 10 week olds and two 2 year olds all together since the younger ones were 4 weeks old. They were all doing fabulously, though the two groups were avoiding each other. I checked on them this morning and all was fine. A couple of hours later I checked again and one of the younger ones was stuck behind the water can. It got out and ran into the coop and I thought it was okay. Then I checked again just about an hour ago and it was dead in the nesting box and there was blood. It looks like it might have injured itself when it was stuck. I feel SO bad. I wish I had checked it out earlier. I don't know if I could have done something. She was such a sweet girl. So now I have the one 10 week old and the two 2 year olds. i'm getting no eggs at all right now because the older ones appear to be moulting. I don't know what my plan of action should be. Maybe just wait a few months to see who is laying and how many eggs we get. Part of me is wanting to start all over with 4 pullets of the same age. But I feel bad just "getting rid" of the ones I have. It was too much work to try to integrate the different ages to do that again.