Brief Answer:
Better get her evaluated by a pediatrician

Detailed Answer:
Hi

Thanks for asking on this platform

I have gone through the query and do understand your concern.
Khansi(cough) in this age can occur due to upper respiratory(throat) infection or infection of lower respiratory tract(lungs).
I would like to know if cough is severe enough to disturb sleep, associated with breathing difficulty or if there is any vomiting following cough. Breathing difficulty like fast breathing or chest wall retraction suggests involvement of lower respiratory tract and should be managed urgently.
Here I would suggest you to get her clinically evaluated by a pediatrician to rule out any involvement of lower respiratory tract.
Giving syrup containing bronchodilator(helps in relieving airway spasm) like salbutamol with sputum thinning agent like Ambroxol helps in relieving cough. In case of lower respiratory tract infection nebulisation or antibiotic may be needed.

I hope this helps.
Please let me know if you have any more questions.
Wishing for your child's rapid recovery.
Regards

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