Low-key, uncontrived, gently amusing, and surprisingly moving: the efforts of 13-year-old Bernie Segal of Plainview, Long Island, to accumulate $99--the amount he needs to run away to join his grandfather in Florida. Bernie, you see, is sure that Grandpa must be lonely--though it's soon clear that Bernie, whose father died not too long ago, is the one who's aching with loneliness. . . especially now that his mother is planning to marry widower Nat Greenberg, an ever-cheerful irritant. Bernie babysits the impossible, hyperactive Wolfe twins. For an hourly fee, he helps his edgy sister Celia learn her lines for the high-school play. (She's Frankie in The Member of the Wedding.) He sells a treasured ring to his rich, epically stingy little sister Gracie. And he even agrees--for a price--to help future stepfather Nat with some parking chores, some therapeutic man-to-man talk emerging in the process. (""It felt good, like the end of a war. I hoped he wouldn't hug me or anything, though, and he didn't."") So, helped by a $50 loan from Grandpa, Bernie does in fact amass the necessary cash--just in time to flee before the Mom/Nat wedding day. But, when it turns out that Grandpa is coming to Long Island for the ceremony, Bernie's big scheme becomes meaningless. And, after assorted family tensions are aired and eased, Bernie comes up with another way to affirm his connection to his dead father: a new middle name. An unusually simple, unforced family story--held firmly back from sentimentality by finely observed everyday details and Bernie's no-nonsense narration.