I have a hen who raised some chicks this summer. They are now four months old and I kept only two, a brown pullet and a brown and white spangled pullet. We ended up selling our cockerel and now only have the mother hen and two pullets. They have a large coop and run and free range at least five or six hours a day now its winter. The problem is the mother hen seems to hate the brown pullet! She will chase her away if the brown one even dares to look at her, and if the brown one comes near the mother will bite at her neck feathers, which obviously distresses the pullet. So far there has been no actual blood drawn or injury but I'm worried for that brown pullet. When they go out free ranging, the mother will stay quite close to the coop and the brown pullet wont come back until sunset some days because she is scared to come near the mother hen. What could be the problem here? I've also noticed that the mother hen really complains about going in the coop to sleep at night if the brown pullet is already in there. She will pace outside and make a lot of noise, like she is looking for somewhere else to sleep. Since I have only three chickens and was planning on keeping them, this is quite upsetting. I'm worried I'm going to have to find the brown pullet a new home.