When 12-year-old Sammy, who has Down’s syndrome, gets lost (while he chases after his stolen bike and its rider, he climbs on the back of a truck and winds up miles from home), he encounters Kevin, a runaway who has been living on his own in the forest. Afraid that Sammy will give him away to the authorities, Kevin won’t let him return home, and eventually the two boys form a tenuous friendship. Although Kevin grows protective, Sammy never loses his determination to leave; when he makes his break, he ends up in danger, and Kevin risks his freedom to save him. In the poignant ending, Sammy, safe at home, holds on to the hope that one day Kevin will come to live with him; no one else believes Kevin exists. Mazer (Twelve Shots, 1997, etc.), keeping the perspective strictly Sammy’s, structures the story so that the boys are two sides of the same coin: one dependent and sweet-natured, but with a stubborn streak, and the other tough, self-reliant, and kind only at the core. Realistically, and with small, honest gestures, each helps the other to grow; Sammy becomes more independent, while Kevin becomes more compassionate. An exciting, unusual survival story, very well told. (b&w illustrations, not seen) (Fiction. 10-14)