I had 12 hens that were about 1 year old. My husband decided we should get 12 more. They were in the chicken house and are now 6 weeks old. Seems old ones are now pecking them to death. I lost 3 since Sunday, and I don't know what to do. Any suggestions? Seems the older ones are also eating them. It is terrible. We thought something was getting in and dragging them out and killing them. But we closed them up all night and didn't let them out them in the pen until mid morning. So from then to three o'clock they killed another. What causes them to do this? We had chickens before and never had this problem even with newly hatched ones. What can I do?