Constipation: This is a common cause of abdominal pain in children, often due to poor bowel habits, low fiber diet, or inadequate fluid intake. It's a likely diagnosis given the age and non-specific symptom of abdominal pain.

Viral Gastroenteritis: Common in children, it can cause abdominal pain, diarrhea, and vomiting. The diagnosis is likely due to the contagious nature of the illness and the exposure to viruses in a school or daycare setting.
Urinary Tract Infection (UTI): UTIs can cause abdominal pain, especially in the lower abdomen, and are more common in girls. The diagnosis is considered due to the potential for severe consequences if left untreated.
Functional Abdominal Pain: This is a common cause of recurrent abdominal pain in children, often related to stress or anxiety. It's considered a likely diagnosis given the age and the potential for psychological factors contributing to the pain.

Appendicitis: Although less common in younger children, appendicitis is a surgical emergency that requires prompt diagnosis and treatment. It's crucial not to miss this diagnosis due to the risk of perforation and peritonitis.
Intussusception: A condition where a part of the intestine telescopes into another, causing bowel obstruction and potentially severe complications. It's essential to consider this diagnosis due to its severity and the need for urgent medical attention.
Pyloric Stenosis: A condition that causes vomiting and abdominal pain due to narrowing of the pylorus, the passage between the stomach and small intestine. It's a critical diagnosis to consider, especially in infants, but can occasionally present in older children.

Inflammatory Bowel Disease (IBD): Conditions like Crohn's disease and ulcerative colitis can cause chronic abdominal pain, diarrhea, and weight loss. Although rare in children, IBD is a significant diagnosis to consider due to its impact on quality of life and the need for long-term management.
Abdominal Malignancies: Although extremely rare, tumors such as Wilms tumor or neuroblastoma can cause abdominal pain in children. These diagnoses are considered due to their severity and the need for prompt treatment.
Henoch-Schönlein Purpura (HSP): A condition that causes abdominal pain, rash, and joint pain due to inflammation of small blood vessels. It's a rare diagnosis to consider, but important due to its potential for severe complications.