I don't know exactly what happened, I had 4 Sapphire gems 12 weeks old. I went in to the garage this morning to let the girls out of their coop and found 1 laying dead and the other 3 standing nearby. They have a 2 story coop with the roost area up top and an attached run at the bottom. we keep it in the garage with an access door that opens into a covered larger run. I keep that access closed at night so nothing from the outside can get into their coop. Anyway I usually keep water and the food they have left during the day. Last night I just left the water as they were in the roost area when I got home. would a break in routine cause them to peck each other? The deceased chicken had blood on her head mostly on one side, and one had a very small blood spot on her comb area, another chicken had a blood spot on her toe, and the last one had a bloody area on her leg. I put an antibiotic salve on all the injuries. I could not see any signs that there had been any attack (feathers all over or straw thrown about) and there was no piles of poop up in the roost area like I normally find in the morning. One of their waterers was off the wall and on top of the dead chicken, the other waterer was half off the wall and all of the chickens were wet. Those were the only indications of struggle. My girls have always huddled together/ roosted right up on each other even though there is plenty of space to spread out / they foraged in a group and stayed pretty close to each other since I got them at 1 week old. I have never seen any aggression between them or bullying from any of them. Any thought as to what could have happened? I didn't see any signs of anything that may have gotten into the coop area, but I am going to close off all my ventilation gaps with hardware cloth today. I guess I felt that they were a bit safer since their coop was housed in the garage.