He would be a symbol of power, grace, and tragedy-but before he was JFK, he was sickly and scrappy, troubled and charming; he was a boy called Jack. To Jack, it seemed as if his brother Joe, not quite two years older, would always triumph-in school, on the playing field, in his father's affections. Jack was the sloppy second son, the witty, disorganized dreamer who could never seem to stay well long enough to muster his talents-a risky failing in...