Over 80% of infant umbilical hernias can heal before the age of two because, as the child grows older, the abdominal muscles gradually develop. The umbilical ring often progressively narrows and closes, so no treatment is actually needed. However, it is usually advisable to prevent the child from crying excessively and to treat any gastroenteric colds and indigestion actively and effectively, to avoid repetitive protrusion of the hernia. If the child still has a noticeable umbilical hernia after the age of two, or if the diameter of the hernia ring exceeds 2cm, it is usually difficult to heal naturally. Surgery might be required, typically involving the removal of the hernia sac and repair of the abdominal wall defect.