I have 4 larger barred rocks (18 months), 3 younger ones (about 14-18 weeks) and some babies (5 weeks). Just yesterday, I headed down at lunchtime to put them up from their morning range, when I came back an hour later I saw a 14-16 weeker roaming out of the coop trying to get back in. This is way out of character bc when I do my walk and whistle around the coop they ALL come running back and jump in the coop. I have 34 chickens and not once have any of them gotten left outside, which tells me she must have been in hiding when I put them up. Anyway, When I put her in, I saw the big girls pecking and bullying her really bad, poor thing hid her head in the corner and just let them keep on at her. I went in the coop to take her out, I put a wire kennel in the coop and put the big birds in there for the night so she wouldn't get killed, I let them all out together this morning and they seemed fine for a few minutes but went straight back to bullying her. She went and hid in a goat pen we have for 4H. Could she possibly be ready to start laying and they sense "another female with hormones" or what ? I'm at a loss as what to do now bc I don't want her getting killed and they have all been so sweet up until this point.