My girls came down out of the coop this morning and all but one appeared fine. One of my bantams though won't eat, she's keeping her back to all the other hens, has all feathers puffed out, won't let me pick her up and just sits there cooing rather mournfully. Any ideas anybody? I'm not super experienced but this is a first for me. Could it be the cold? Our temperature really dropped last night. Thanks.