Brief Answer:
As explained below

Detailed Answer:
Hello, and welcome to 'Ask a Doctor'.

Thanks for posting your query. I have gone through your query . If symptoms aren't bothering your child, they don't need medicine or any treatment. Many children with a cough or cold are happy, play fine and sleep well.

You can give him syp. Sinarest 0.5 ml twice a day and crocin drops if he is having fever 0.5 ml as and when required.
For cough give him clear warm liquids, apple juice or lemon juice etc. Give him adequate fluids.
Nasal saline drops before feeding and sleeping will help clear nose blocks.
Steam inhalation helps if you can make him sit for 10 to 25 mins.

I hope this helps. Please feel free to discuss further if any.
Regards,

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