In a 6-year-old, repeated abdominal pain can be due to constipation, gas, worms, indigestion, urine infection, or stress/anxiety.
Do next:
Give plenty of water, fiber-rich food, avoid junk/spicy food, and check stool pattern. Consult a pediatrician for examination and tests like stool test, urine test, and deworming advice.
Go urgently if severe pain, fever, vomiting, blood in stool, weight loss, or pain on right lower side.
Next Steps
You can check for ultrasound whole abdomen.