Thanks for your query
could be due to medication or viral in nature,
I suggest you to mantain proper hydration,give oral rehydration solution sip by sip after each loose stool
,coconut water,lemon water,curd,banana,boiled potato.
Also give lactobacillus
sachet for 2 to 3 days and zinc for 14 days.
In case symptoms persist get her examined by pediatrician
Wishing your child good health