I am bumping this because I am literally in the same situation. One of my 3 polish is being pecked at as well. Mine are 10 weeks. They are in the coop by night, run by day. I cannot tell who is doing it as it is done at night. A second coop is not my first choice. Yes honey now that you built a coop, a run, a barn and are now in the middle of helping me build horse fencing and a riding ring you need to put up another coop as well. I think divorce would come up.