The 23-year-old amateur runner and adventurer, who completed his first marathon in the second grade, kept a rigorous training schedule. Then, wracked by debilitating diarrhea, cramping, and pain, Rob was diagnosed with Crohn's disease with ulcerative colitis, inflammatory bowel diseases. Over the next year and a half, Rob's condition worsened. His weight plummeted — from 185 pounds to his lightest recorded weight of 105 — and it became clear that his large intestine needed to be removed. Read more.