So, I checked my chooks this afternoon and one stayed under the coop for a bit longer than the rest, considering I threw cantaloupe in for them. She finally came out but her legs were partially bent, i.e. she wasn't walking on her feet but her feet and the legs below the "hock" or elbow. She ate but sat down to eat (see pic) and didn't seem to want to stand up. I picked her up and she didn't really struggle. After I put her back, she seemed fine but went back under the coop to lay down. This isn't normal for any of them but I'm at a loss as to what this could mean. All fed the same things, no trauma from anyone/thing, eating and drinking. Just seems to have a little less energy than the others, almost like she's avoiding them. They are 4 month-old RIR pullets. Suggestions? TIA!