Yes I am 100% sure it is her egg because while the others lay pale brown eggs hers are a deep brown and she lays every day just about and the others do not but I agree she looks sick but she eats heartedly and excitedly but maybe not as much as before and she lays around a lot an walks more slowly. I have spent hundreds of dollars on my chickens and every one of them died anyway. The vet seemed puzzled as to what to do with chickens. I am on a fixed income so I am truly at the end of my money. It is just an enigma I don’t know what to do