I have this one RIR chick that is experiencing some odd behaviors and I think that she might be injured somehow. I was watching the chicks in their pen and noticed this one chick just closed one of her eyes and then slowly listed to that side. She eventually fell off after 3 or 4 seconds and took a tumble down two level which is about a foot or so. It seems like her breathing is a little labored. She can get up and walk around and is attentive when you nudge her but if you leave her alone she just closes that one eye, slowly sit down, and list towards the one side. What bothers me as well as this behavior is that a few of the other chicks are now starting to peck at her back and head. Should I seperate her? It doesn't seem that they are doing it maliciously and she doesn't seem to mind. Any help would be greatly appreciated.