I'm 99.999% sure that scarlet is a she. She never showed ANY aggression whatsoever or even was the most dominant of the sisters, and even now shows zero aggression or posturing towards the other two sisters. but she saw blood and just went for her.
I was thinking now that happy feet is...
I was out in the barn when it happened. I'm not sure how exactly she scratched her comb. I am guessing it was trying to squeeze places she has become too large to fit. The initial scratch was very small and shallow but it bled a tiny bit and her sister who had up until this point never showed...