Did it look like the blood was mixed in with her stools or more just on the outside?
If it seems that it was mixed in with the feces than she's probably got some sort of intestinal parasite, irritation or illness.
But if it seems like it's just on the outside it may be the rawhide irratated her intestinal tract. Or even if the stool was very formed (hard) it may be that part of her rectum was torn a little bit (the rawhide could cause that too).
Glad to hear she's all better. I hope she continues to do well. I love that girl!
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