She was only 2 years old. She was going through her moult and then I noticed she was behaving strangely. She wasn't eating, not sure about drinking, she was very light, not socializing with the other chickens, the other chickens didn't want to be near her, very little poop, just a few dark green drops, stumbly (whenever I picked her up and put her back down she would stumble), head down, tail down, face, comb, and wattles very pale, eyes watery/bubbly, and not laying. I knows hens don't normally lay when they moult. The other hens going through a moult aren't lethargic like she was. Anyways when I found her in the morning, I found her in the very place I put her where she normally likes to sleep, stiff as a rock. Maybe from the cold. Anyone have a clue? Whatever caused it, is it contagious to my other birds?