About a decade ago, when I was running the emergency department at Rady Children’s Hospital in San Diego, a woman showed up with her seven-year-old grandson who had been suffering from unexplained fevers and pain that moved from one leg to the other. Ours was the fourth ED the family had come to for help. At each prior one, the staff obtained an X-ray which proved to be normal and the family was advised to follow up with the child’s pediatrician. When I examined the child, he had no fever or leg pain. He seemed fine, and I was in “busy mode” — a trauma was coming in and I had just done a lumbar puncture on a patient with meningitis. I almost sent the boy on his way just as the other ED doctors had. But then I paused; the family had sought out a different ED each time, uncomfortable with the non-diagnosis. They knew something was wrong. So I decided to try a different approach that day. I asked the grandmother what her greatest concern was. She immediately responded that she feared her grandson had cancer. A lightbulb went off. Roving leg pain, normal X-rays, unexplained fever — it could be cancer. I suggested that we obtain a blood test. Sure enough, the boy had leukemia. I would love to think that I was a brilliant enough doctor to have seen it on my own, but frankly I would have missed it just like the previous physicians if I hadn’t asked the question and allowed the grandmother to voice her inner fear.