We got 12 chicks from rural king about 3 weeks ago. A mixture of different breeds. One of our barred rocks is less than half the size of the other barred rocks and other chicks. She seems healthy, she eats really good, maybe more than the others in fact. She has good energy and doesn't act sick or anything in any way. She is just way smaller than the others and has almost no feathers where as the others have wing feathers and starting tail feathers. She gets pushed around and ran over sometimes in the brooder. Why would her growth be so stunted? Is there anything we can do to help her catch up to the others?