We went out to the coop to play with the hens this evening like we always do and our Black Sex Link was dead in the coop. Face down and stiff. Eyes mostly closed and a tiny bald spot on her chest. Other than that not a mark on her. No signs of injury or trauma at all. She was only about eight months old. Yesterday she went for her afternoon walk, took her big dust bath, was eating/running/playing, getting petted and being a happy chicken. We are devastated and completely perplexed. Does anyone have any ideas? Do we need to do anything to protect the rest of the flock?