This chick will be 8 weeks old this weekend. She has always been the runt of the 16 that hatched. She is much smaller than the others, and has never seemed to grow new feathers. I have watched her quite a bit. She eats and drinks well and no one appears to picking on her or pecking at her. However, you can see she has no real feathers on her back and wings. I thought it could be some kind of parasite, but she has always looked like this and all of the other chicks are fully and beautifully feathered. Should I be worried? What could this be and what can I do to help?