Hello! Thank you for the query. You should be very careful treating your kids at home. Young persons can take much less than an adult if it is about gastrointestinal issues. Theirs bodies are weaker. Yours symptoms are most likely caused by viral or bacterial infection of the gastrointestinal tract. Most of such cases does not need medical attention and goes away in a day or two. Lack of appetite after such infection is a normal thing. It is because intestines bacteria needs to be rebuild to maintain the balance of the gastrointestinal tract. It can take up to a week or so. During that time, You should have mild diet, avoid spicy foods, fatty foods. Probiotic should be taken as well. If the symptoms wont go away in a week or so, you should visit a doctor. Hope this will help. Regards.