Umbilical hernia mainly manifests in children as a bulge at the belly button, primarily containing small intestine. If an umbilical hernia is not treated in a timely manner, it may gradually enlarge when the child cries or when intra-abdominal pressure increases, leading to more of the small intestine protruding outside of the abdominal cavity. This can potentially cause localized intestinal obstruction, impacting the child's intestinal absorption capabilities and leading to weight loss. If a significant portion of the intestine protrudes and becomes incarcerated, it could cause intestinal obstruction or necrosis, necessitating surgical removal of the necrotic intestine in a hospital.