Hey dear i understand ur problem as weak immunity s common thing in kids..same happens to my devrani baby her friend advised her to for influenza vacin once in a year nd advised for healthy diet aa add milk ,cheese ,butter ,paneer ,green vegetables, fresh fruits ,nuts ,oats ,ragi,eggs in diet too ..she add these in diet its really work for him. U can try it dear..nd see what another expert moms said more. U can share ur expirence too.