I have a Rhode Island Red that I adopted with 6 others in her flock last year from a man going through cancer treatment, and I am not sure of the ages...I have had them for a year, and they were laying when I took them They have been a great flock and are producing well. For the last two days one of the hens has been staying to herself, with her feathers puffed up slightly. She is out and about, eating and drinking, but just looking like she doesn't feel right. Tonight, they were all walking with me and two of the others were pecking at her and treating her meanly. I understand pecking order, but I have not seen them act this way before. If she is ill, would the others know it and try to isolate her? Any help would be appreciated.