Brief Answer:
Give plenty of fluids, watch for signs of dehydration

Detailed Answer:
Hi

Thanks for asking on this platform

Most common cause of diarrhea in this age is some viral infection/food allergy.
I won't get overly worried if child is taking orally well(there is no vomiting), passing urine and is otherwise active and playful.
Give plenty of fluids in the form of ORS, plain water, coconut water, rice water, dal water etc. Avoid giving juice, sugary fluids, home made ORS.
Watch for signs of dehydration like excessive irritability, lethargy, poor feeding, decreased urine output, shrunken eyes, dry skin etc.
If you are noticing any please consult your pediatrician immediately.
Giving probiotics like Enterogermina helps in maintaining gut flora. Give zinc syrup for early recovery.

I hope this helps.
Please let me know if you have any more questions.
Regards

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