[Ponyup]

I've had cats alot and it's very rare for them to get diarhea. It usually comes from drinking milk or eating something high in fat. Has she gotten into anything that she shouldn't have. It also very weird that if she's litter trained that all of a sudden she would stop using it all together. First thing i would do is pour out all the litter in the box and put in fresh. Is she current on all her shots?