Functional abdominal pain: This is a common condition in children, often presenting with recurrent abdominal pain, including around the umbilical area, without an identifiable cause. It's related to stress, anxiety, or changes in bowel habits.

Constipation: Can cause abdominal pain that may be perceived around the umbilical area due to the buildup of stool in the intestines.
Gastroenteritis: Inflammation of the stomach and intestines, usually due to infection, can cause abdominal pain, including around the umbilicus.
Urinary Tract Infection (UTI): While more common in girls, UTIs can cause abdominal pain, including in the umbilical area, especially if the infection involves the kidneys.

Appendicitis: Although less common in this age group, appendicitis can present with abdominal pain that initially may be diffuse or around the umbilicus before localizing to the right lower quadrant.
Intussusception: A condition where a part of the intestine slides into an adjacent part, which can cause severe abdominal pain, vomiting, and bloody stools. It's a medical emergency.
Pneumonia: Basilar pneumonia can refer pain to the abdomen, including the umbilical area, especially if the diaphragm is irritated.

Meckel's Diverticulum: A congenital anomaly of the small intestine that can cause pain, bleeding, or obstruction, though it's less common.
Inflammatory Bowel Disease (IBD): Conditions like Crohn's disease or ulcerative colitis can cause chronic abdominal pain, including around the umbilicus, though they are less common in young children.
Ovarian torsion or ovarian cyst: In girls, these conditions can cause severe abdominal pain, though they are rare and usually associated with other symptoms like nausea and vomiting.