We recent moved. For one week, my free range girls were kept in their run. The day we went out to move the coop, we found one girl missing feathers and bloody. We have separated her to give her time to heal. That started Dec 7. Finally has all her feathers and even laying. Tried to introduce her today and the flock attacked her. We had to jump in to get her out. Why are they doing this all of a sudden?