From whelping box to hand-off, the cost to train one of these special dogs: $20,000. This blog, updated weekly, chronicles the author’s ongoing research, and often will take detours, exploring the world of these four-legged peanut detection machines and other working dogs, the tumultuous and sometimes tragic lives of the kids they’re born to save, the controversy swirling around peanut-free schools, and what physicians know, and don’t know, about the medical mystery of peanut allergy, and the quest for a cure.