the frequency of the stool indicates there is diarrhoea even if the consistency is not watery, giving an antibiotic will increase the problem because most of these antibiotics can cause diarrhoea as a side effect and killing the beneficial bacteria in the intestines. the fact that ( stooling ) occur after eating indicates that this child has what is called exagerated gastrocolic reflex , which is a normal physiology but increased by the hyperactive bowel from an offending agent . I recommend doing a stool analysis and culture to exclude bacteria or parasite . in the mean time you need to increase fiber diet to bulk the stool, and water to prevent dehydration , you can use smecta sachets which can decrease the amount of stool . I hope this helps