I have been out of town for 5 days. My father in law cared for my flock while i was away and everyone was good. This morning I went to let them out and one of my favorite hens was dead on the coop floor. She was 1.5 yrs old and acting totally normal. She had some feathers missing maybe from the rooster. I had checked her for mites and lice but didn't see any. Do hens just randomly die? I am so upset and heartbroken.