We have 7 hens which we bought as chicks about 1.5 years ago. Two Yellow Sex-linked, two Wyandottes, and three RI Reds. They have been henpecking the runt RI red for the last year, and picked a bit on the large Wyandotte for about a month this past spring, then laid off. Over the last four days (OR nights), the other Wyandotte (who has never been visibly pecked before) has lost of all of her neck feathers, many of her head feathers, and is starting to lose feathers on the top of her back, between the wings. my hunch is that she is being pecked aggressively, or could it be some kind of illness? Please give us some advice. Thanks!