I have 4x8 coop and a 113 sq ft run in which my 5 birds are confined in the mornings. My birds free range several hours every day. My BO went broody, so we gave her a chick that she adopted. BO has been a great mama, but her chick is almost 6 weeks old. Mama has started laying again and has been leaving the chick alone more and more. What I've noticed is that my 3 other pullets, almost 10 months old, really don't want anything to do with the chick. They chase her and peck at her sometimes whenever confined in the run. Mama doesn't always intervene like she used to. I have places where the chick can run to get away from the older ladies, but she would much prefer to be with Mama. Luckily, she hasn't been injured, but it's sure tough to watch. How much bullying is too much? And when/how should I intervene (if at all)?