Hi thanks for contacting HCM.... According to history he has frequent cough and chest congestion .... So there could be chance of allergic infections ..... CBC can be done while congestion ... If show high eosinophilia then allergic infection and high lymphocytes then viral ... Symptomatic management done .... Antihistaminic drug given for decongestion... If rhonchi heard then bronchodilator levolin given.... If thigh phlegm present then for bacterial infection antibiotic can given otherwise no need for it in allergic condition... Allergen test for him can be done .... Give him some fruits daily ... Consult pediatric doctor with keeping my answer in mind .... Take care