Hello As you mentioned that your son is just 15 months and having recurrent throat infection , tonsillitis , strep , & pneumonia . As I have noted that children in this age group usually got allergy and this causes infection also . Usually there develop whistling sound ( wheezing ) , running nose , eyes tears and these symptoms recurs frequently . This is a very common problem faced by this age group patient. When such patient visit I only prescribe them to take montelukast+bambuterol ( 0.2 mg each / kg body weight ) syrup ,once or twice in day , dependin on severity of infection. If tonsillitis ( throat infection ) I advise my patient to take levofloxacin 10 mg / kg body weight once in day orally , syrup . Since this is a prescription medicine , so consult your physician and for prescription. Hot coffee and steam inhalation also provide much needed relief at once. When your child will attain the age 14 -15 years , symptoms subsides ( after puberty ). Need not to worry this is very common. Good luck.