I got some free chickens and have been nursing them back to health. They were cared for by a very old woman, who kept 3 roosters and 6 hens in a 10ft by 4 ft run. That was mounds of poop and fed them a flock block. She passed and the chickens need a new home. When I got them they all had their feathers missing like this one, but it's been a few weeks now and almost the feathers have grown back in except on one hen. She looks exactly the same as when I brought her home. I got rid of two roosters, just have one. So I dont think hes the problem. I've watched and hes not aggressive with them. They free range and have a nice size coop. So I dont think its stress. They get organic layer feed, scratch feed, kitchen scraps, free choice calcium and kelp. I'm new to chickens so can some help me help this hen grow feathers because cold weather is coming!