|Jon Boling sang as he steered his cataraft down the Middle Fork of the Salmon River on June 3. His little ditty parodied the tune of an old Toys-R-Us jingle: "I don't want to grow up; I'm a Middle Fork kid!" He was giddy.These were the moments he lived for -- a beautiful river, a cooler full of good beer, the company of friends.Life doesn't get any better.As a Southerner who migrated west in pursuit of a life lived to the fullest, Boling relished the moment.But less than two hours into a five-day trip, Boling's boat flipped in a rapid.His hulking frame was no match for the icy waters. His heart gave out. Boling was 34 years old.This is the story of his final voyage.