Thanks for your query.
Your child is having diarrhea which could be viral or bacterial or protozoal in nature and takes few days to settle.
Most important is to maintain hydration.
Give oral rehydration solution sip by sip after each loose stool
,give coconut water,lemonade.curd.buttermilk.rice porridge.banana.boiled potato.
like lactobaccilus for 2 to 3 days.
Monitor features of dehydration
like increades thirst/decreased urine output/lethargy/sunken eyes/decreased skin turgor and in case you find any get him evaluated by pediatrician
for further management.
Wishing your child good health.