It's a myth that giving curd banana will cause cold.

There is no evidence that banana and chikoo can worsen a cold. Don't listen to non doctors around you. This is likely a viral respiratory infection. It may take 7 to 10 days for the cough and cold to go away. Visit a pediatrician for check up and guidance.

Yes one can feed these fruits unless the child is allergic to them… Always consult your doctor before using nebulisation

Consult with Pediatrician physically for further evaluation and treatment

In a 6 months old baby, give only nasal saline drops for cold and cough. Most of the times it is the increased mucus production in response to cold and dry air and not infection. And when it is infective and baby is active and feeding well, it is mostly viral. Cough syrups are not recommended in children less than 4 years of age You can very well give him banana, curd or any other fruit. These do not cause cough or cold. As I told, cough and cold with or without fever are due to viral infection mostly and not related to any food items.