Bret and Kim Stafford, the oldest children of the poet and pacifist William Stafford, were pals. Bret was the good son, the obedient public servant, Kim the itinerant wanderer. In this family of two parent teachers, with its intermittent celebration of "talking recklessly," there was a code of silence about hard things: "Why tell what hurts?" As childhood pleasures ebbed, this reticence took its toll on Bret, unable to reveal his troubles. Against...