Apples actually help move the bowels, I wouldn't do that if I were you. Yogurt yogurt and more yogurt. All the yogurt she will eat. Yogurt has all the healthy bacteria the intestines need to help stop the diarrhea. My sons pediatrician says its the best natural remedy and as much of it as they want to eat is fine. At 10 months the cows milk used in yogurt really is no big deal.
Also steer clear of anything grape related-it will also continue to move the bowels. Grapes, raisans, grape juice, apple juice, apples, all bad...yogurt! It was my saving grace for the first few years of my sons life, he was sick so often and constantly on antibiotics which if course caused diarrhea, and the yogurt helped tremendously.