Well come to HCM I really appreciate your concern, in pediatric age group of patients most of the diarrhea are self limiting and may not need any treatment from any of the system of medicines, passing of the stool three to four time in day is normal one, only thing is care need to be taken for dehydration. If the symptoms persist then stool needs to be sent for culture sensitivity, routine stool examination may not helps, till then lyophilized Lactobacillus can be tried, at the most it could be protozoa infection it can be well treated with specific drug if found positive hope this information helps.