There are many reasons why an eleven month old baby who has diarrhea can have diarrhea. One is symptomatic diarrhea. If the baby is cold, upper respiratory tract infection and other triggers, there will be a slight diarrhea phenomenon. At this time, the number of stools will not be too much, stools will be a little thinner than usual, is symptomatic diarrhea. This is symptomatic diarrhea. This kind of diarrhea usually improves with the improvement of the primary disease. The other is viral enteritis, the most common is rotavirus enteritis, rotavirus enteritis occurs in six months to two years old babies, autumn and winter is more common, the stools will be like Xieshui or eggdrop soup. The number of stools can vary from five or six to more than ten, and some babies also have a low-grade fever, which can be confirmed by routine stool tests and rotavirus. The other is bacterial enteritis. If your baby’s stools contain a lot of mucus or blood, and if there are a lot of white blood cells in the stool, then bacterial enteritis is present.