my niece is 4 years old and he is having cough from last 4 months. Doctors say that it is allergic and will stop with growing age. we have consulted many doctors but not getting reliefed. He has no cold but have only cough. we are not providing him cold and sour things but still he had cough whole night at interval of 1/2 hours. cough starts suddenly at any time. I am not getting any solution.