Just found my Bantam EE girl cold and dead, face down on the coop floor beneath the roost bar when I opened the coop up. Everyone else looks bright eyed and bushy tailed. She laid an egg yesterday, and was almost a daily layer. She was alive at 9:30 last night when I locked everyone up. Crop was empty when I checked her body, but had been full last night. No apparent injuries, bird was in good weight and seemingly in good health for the last 11 months. What could make a bird drop dead like this? Anything I should be looking out for in my other birds?? Everyone is fed Purina flock raiser crumbles, has access to oyster shell, fresh water cleaned daily, and lives in a 16x32 run on dirt, straw, and sand. I have 23 remaining bantams, some of which are her own chicks.