Thanks for your query.
She is most likely suffering from viral diarrhea
The main issue in management is to avoid dehydration
& giving her small drinks frequently will definitely help.
If she is throwing up very frequently (every hour or so),has not passed urine for 6 hrs, has sunken eyes or no tear production ,is very irritable , you should take her to ER.
If not so ill or none of the above signs of dehydration continue with small sips of ORS
,buttermilk,coconut water etc.
Wishing her a speedy recovery