We lost one of our wyandotte/leghorn cross hens on Sunday and I still have no idea why! She was fine and frisky in the morning when we fed them, but when I came out around 1 to let the girls out for a rummage in the garden she was lying in the run, already stiff! No signs of injury, she wasn't egg-bound that I could tell (no hard lumps, etc. though her vent did look a bit distended), and had been laying and acting healthy before that. I've been keeping a close eye on my other girls but nobody seems to be showing any signs of something wrong. Mostly I'm just sad and stunned! She wasn't even quite one year old and she was such a pleasant, sweet, friendly girl and a great layer.