I checked on my chicks today and found one of them wasn't running around like she usually does and when I picked her up I saw that her whole butt was missing all of it's feathers and it was bloody I don't know what happened! I had to put her out of her misery and it was so sad. I have two groups of chicks in one brooder and they're two different ages, but they've always gotten along and there hasn't been many issues with pecking. Did one of the older chicks just manage to draw blood and keep pecking or did something else happen that I should be concerned about with the other chicks? I feel so terrible.