In Part 2 of this pediatric abdominal pain Episode - Pediatric Gastroenteritis, Constipation Bowel Obstruction, Dr. Anna Jarvis, Canada's mother of pediatric emergency medicine and Dr. Stephen Freedman, one of Canada's pre-eminent researchers in pediatric GI emergencies, discuss the assessment, work-up and treatment of pediatric gastroenteritis, with particular attention to gastroenteritis acute abdomen mimics, how best to assess hydration status, the nuances of the use of ondansetron and the prose and cons of various rehydration methods. A detailed discussion of the most common and lethal causes of acute abdomen bowel obstruction in pediatrics follows, including intussesception and midgut volvulus. Finally, the differential diagnosis and best management of the most common cause of pediatric abdominal pain, constipation, is reviewed.