I have a Cochin chick that was purchased a week ago today. I am not sure how old she is; she is small/hand-sized, but has some adult feathers. Two days ago, I picked her up and heard some cracking breaths. I held her close to listen and she sneezed. A very small amount of clear, watery liquid came from her nostrils. After this, her breathing sounds were clear. Yesterday I picked her up again and she had the crackling sounds again. She sneezed and was still slightly raspy, but I dont remember any discharge. Other than this, she is completely normal. She is curious and active, runs around and flutters, has no discharge other than the clear, watery stuff a few days ago (nothing thick or sticky). Her vent is clean and she does not seem swollen anywhere. Her poops are normal, as far as I can tell. I have seen her eat (medicated Purina Start & Grow) and drink. She lives in an 8x8 coop with five other chicks (four older than she is, one about the same age) and has access all day to an 8x16 run. They were all purchased from the same feed store, just a week apart. None of the other chicks have any symptoms. Does this sound like anything to be terribly concerned about? Should I just keep an eye on her to make sure she doesnt get any worse? I looked at some websites of common diseases, and most of what they describe has more symptoms, so Im not exactly sure what she might have. Is this maybe something that will go away in time? Should/can I buy some antibiotics for her? Thanks in advance.