When a 4-month-old baby scratches the same ear frequently, watch out for the following: First, look carefully for boils, eczema, hives or swollen lymph nodes around this ear. Second, look carefully at the outer ear canal of your baby’s ear for foreign bodies, boils, or pus coming out. Third, pay attention to the possibility that the baby has a disease such as otitis media or a tumor inside this ear. Fourth, also focus on intracranial problems, especially on this side of the brain that is often scratched by the same one, and see a pediatric neurology clinic, which requires a head imaging test. Regardless of which of the above causes, if such a situation occurs frequently and lasts for a long time, you must seek medical attention in a timely manner.