Duplicates of the gastrointestinal tract are rare malformations, which most commonly become symptomatic and are diagnosed during the first two years of life. In this case report, we will recount the story of a 3-year-old patient, who introduced himself with lifelong, intractable obstipation and intermittently emanating stool from the penis. Intraoperatively a complete duplicate of the colon frame with rectovesical fistula became evident. After three procedures, a temporary ostomy, and a final separation of the septum via multiple colostomy and occlusion of the fistula, the boy is now free of complaints.