My boy was 4 years 10 months old he was suffering with heavy cough at night and early morning and also we have went to doctor when we use medicine the cough was reducing after stopping medicine then again he get cough it was reapting from last few months nd we have taken x ray and blood test also but they are normal in x ray it shows light pneumonia.After using medicine it was normal.But my kid cough was not curing please help me am much worried about him