Hi and thanks for your question, I will start by commenting that the commonest cause of diarrhea, especially watery , in children of this age is viral. This usually simply involved treatment with oral rehydration solution and adopting a proper cleanliness attitudes to avoid child being contaminated by this virus, generally rotavirus. Bacterial involvement usually involves some high fever, alteration of the general health condition of the child and at times bloody stool. However, might not be the case in all situations. Prescription of antibiotics actually comes in when any of these severity criteria are noticed. A full blood count, stool examination, culture and anti biotic sensitivity tests are usually appropriate. I will suggest, based on the results, the child should be put on first line appropriate antibiotics like Bactrim or Ampicilline (against Shigella) probably, as a stool culture and sensitivity tests are being done to be more specific in choice of the antibiotic, in case its actually a bacterial infection. Giving the child oral re-hydration solutions and maintenance of proper hygienic conditions are the priorities for now, as you await to meet a pediatrician for the stool culture to be done. Thanks and best regards, Luchuo, MD.