The notion that ""well programmed robots. . . have lives of their own"" might make Asimov wince. But even though Jack's, Dad worries about the implications of buying his son a robot best friend, this is basically a domestic comedy wherein not-quite-human, very expensive Danny wins acceptance despite the strain he places on the family budget. The clincher comes when a gang of kidnappers can't tell the real boy from the robot and Danny must rescue Jack from being robotnapped. But the fun lies mostly in Slote's easygoing depiction of parents discomfited by the arrival of a perfect son who needs neither disciplining nor Mom's home cooking. Engagingly programmed to prove that kids know best.