your son is suffering from acute gastroenteritis
Give him plenty of water,lemon juice,electral powder,as dehydration
is very common if loose motions does not control.
Give rice,curd and buttermilk.
Give some anti diarrheal syrup to stop diarrhoeea.
If loose motions does not subside and he felt more pale and dry tongue take him to doctor without delay to combat dehydration.
ok and bye.