Brief Answer:
Possibly a viral infection.

Detailed Answer:
Thanks for using the Ask a Doctor service.

I have gone carefully through the details and understand your concern. Treatment is supportive and usually comprises of antiallergic medication like Cetirizine Drops, and saline nasal drops for blocked nose. You can give the Drop that you have mentioned (attached image).

You need to give steam inhalation to your child. It helps in reducing the congestion and thereby the cough. Just sit with the child on your lap and place the source of steam before you. The water vapor will be in the air and automatically the child will breathe it in. Water vapor will reach deep inside and would help in diluting the cough and thus would provide relief.

If your child is otherwise active and playful, I would not be concerned. If not, it would be a good idea to visit a doctor and to get the child evaluated. If the respiratory rate is greater than or equal to 40 breaths/min you would need to take her to a doctor for the possibility of underlying pneumonia. If the rate is lesser, you need not worry.

I hope that I could clear your doubts. Usually the symptoms resolve in a week or so.

Feel free to write back.

Regards

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