A 4-year-old child has been experiencing bowel movements every three days, with abdominal pain before each one. The stool is hard at the beginning, followed by loose, soft, and shapeless material. Pain decreases after defecation but recurs soon after. The child has taken ‘Enterococcus faecalis and Bifidobacterium longum granules’ for two days, which temporarily relieved the symptoms, but they returned after stopping the medication. Inquire about the cause and appropriate medication treatment.