Hello, If you believe that constipation is not the cause, there may be other underlying issues that need to be addressed. Here are a few things that could potentially be causing their symptoms: * Food allergies or sensitivities: Some people are sensitive or allergic to certain types of food, which can cause stomach pain and upset after eating or drinking. * Acid reflux: Acid reflux is a common condition that can cause stomach pain and discomfort after eating. This occurs when stomach acid flows back into the esophagus. You may want to try having your children avoid foods that trigger acid reflux, such as spicy or acidic foods, and elevate the head of their bed to prevent acid reflux at night. * Stress or anxiety: Stress and anxiety can also cause stomach pain and discomfort. These are the potential causes of your children s symptoms. dealing such patients at my clinic, you would always find a cause for which i would do certain tests like ultrasound abdomen. I would suggest to talk to a children doctor and make a plan. In the meantime, you may want to try having your children eat smaller, more frequent meals and avoid large meals close to bedtime. You can also try giving them over-the-counter antacids or pain relievers to help alleviate their symptoms. Take care. Hope I have answered your question. Let me know if I can assist you further. Regards, Dr. Zia Ul Haq, General & Family Physician