I bought 6 chicks from a local breeder (all vaccinated and a few days old) 10 days ago, and one of them doesn't seem to be doing well. She was always a little smaller than the others, but now I'm noticing an even bigger difference in size, and her feathers aren't coming in like the others' are. I don't see anything noticeably wrong with her, but more and more she just stands by herself and kind of dozes. She's either a Barnvelder or a cream leg bar, if that matters. Any tips or ideas? She was of course my favorite!