I am a first time chicken owner. I have 3 Buff Orpingtons, 3 black sexlinks, and 3 Light Brahmas. They were hatched may 1st and I have raised them since. They all are hens and have been laying for about 6 weeks now. This morning when I went to collect eggs, one of the Buff Orppingtons was dead. It appeared that it had happened not long before I got there. Her body was still warm. She had no injuries on her body. I was wondering if she had a heart attack or something similar. Can she have gotten startled and fly into a wall? Can someone maybe give me a clue?