Thanks for your query.
Your child is having enteritis
which can be viral or bacterial in nature,
I advise you to get him evaluated by a pediatrician
as he needs stool examination and he may need a course of antibiotics.
In the mean time give him lactobaccilus sachet for 2 to 3 days.give plenty of fluids,coconut water,curd,banana,boiled potato,
Wishing your son good health