Hi everyone, We have just 3 hens and have two chicks that are in a separate pen getting ready to be introduced to the others. We recently brought the chicks to the yard and let them poke about a bit, supervised. Since then, one of the hens, that have been living together peacefully for the last year, started picking on another, and over the course of several days made her neck bleed and we had to put her in a separate pen to let her heal. I don't understand why all of a sudden this one hen, who is 4 years old and never shown any aggression, decided to pick on this other hen. I thought it might be the introduction of the chicks, but I'm not sure what to do from here. The picked on hen fluffs up, squacks and tries to get away if her former friend even comes near her now. They're such a small group it's breaking my heart. . Any ideas?