Has she gotten any shots/meds lately? Has she eaten anything she wasn't supposed to? Any vomiting? How much does she weigh? Depending on her weight, you can give her 1-2 tsp's of Pepto Bismol and if her Diarrhea doesn't stop within a day (after taking the Pepto, it SHOULD stop WAY before that..) I would take her to the vet and have him check her out just to make sure everything is ok.
If she weighs 4lbs or more, give her 2 tsp's of Pepto, if she weighs 3lbs or less, give her only 1 tsp
