One of the chicks seems to be having small seisures. It flips over on it's back and one leg comes up to it's head and it shakes/scratches and cries for a few seconds. I pick it up and after it stops, there doesn't seem to be anything wrong with it. It just goes back to eating. I thought it was just because she was a little smaller then the others, she was getting run over a lot and having trouble getting righted, but just now, we had her out by herself and she was pecking along and then just fell over on her back and started with the shaking and crying again. It only lasted a few seconds and then she was fine again. Does anybody know what this could be?