I originally bought 5 pullets ranging in age from a few days old to 4 weeks old. I got them all within a day of each other and they were a perfectly happy little flock from the very beginning. The following weekend I got three older pullets (12 wks) and they went directly into our newly built run and coop while the younger girls stayed inside in a dog kennel at night and in a small separate run during the day. For two weeks I would let the little ones free range outside around the run the older ones were in. So they have seen each other quite a lot. Well the oldest of the original 5 are now feathered out and the dog kennel has gotten pretty crowded, so I decided to move those two (now 7 wks) in with the bigger girls (now 14 wks). None of them were happy with this change! I let them free range together yesterday afternoon and they pretty much stayed in two separate groups. The big girls would occasionally rush the little ones and give them a good peck, at which point the babies would run to me for protection. Once it started getting dark I put the three smallest in the dog kennel and took them inside, and put the two that I am moving in the run with the big girls. They got pecked and chased quite a bit and seemed pretty scared. They kept calling me with the most pitiful chirps. They big girls went in to the coop, but the little ones stayed out side. Ever time I would put them in the coop they'd come right back out. I eventually got them in and closed the coop. Crossed my fingers and went to bed. I was relieved that every one was OK this morning. As soon as they came out, the pecking and chasing began again. The young ones would fly up to my lap to get away from the big guys and only fly back down once they moved to the other end of the run. When I left the run, the babies tried to follow me and I could hear them calling me all the way into the house! I feel like such a bad mom! So my questions is, how long does it take for the bullying to ease up and for the new girls to get accepted? It makes me sad seeing them huddled alone in the corner of the run while the big girls mingle with each other. Plus The big girls peck HARD. I'm hoping they don't hurt the little ones. Do hens ever try to KILL new birds? Or do they just bully them alot?