I have 6 baby chicks all 15 days old. The past few days my one chick who's feathers are growing a lot faster and shes growing more than the others has been keeping to herself. She's a lot more skittish than the others, won't take treats from me, and stays in the opposite side of their house. They only time she's near them is when they are all sleeping. Should I be worried? I'm new to chickens and this seems odd to me but maybe I'm worried over nothing?