Following 1999's Twinship, this novel about a group of misfits trying to deal with the conundrum of a man who has "gone and become a baby" is again enlivened by Foos's offbeat sense of humor and kooky characterizations. When doll maker Chloe Taft's Spiderman-obsessed brother Irv literally turns into a baby (though his head is still adult-size), she must find a way of getting him back to normal. The family is already peculiar enough: Nathan, Chloe's husband, is a party planner who jots down bits of dialogue on index cards to give to those at a loss for words; her uncanny father, "The Big E," is a 65-year-old retired power lifter. Woven into this wackiness are media reports about Long Island homecoming queen Darlene Mulholland, who, after a secret pregnancy, delivered a baby in the high school locker room, then rushed out to accept her crown ("I did what any girl would do"). Insisting that the infant has been abducted, Darlene's mother commissions Chloe to design a "replacement." Meanwhile, Irv's wife, Ruth, also pregnant, has left him, but compassionate Chloe, between feeding her brother and changing his diaper, reunites the pair and arranges for a priest to exorcise Irv's demons and bring him back to normal. When that attempt fails, a birthday party fit for a superhero finally does the trick in a rousing conclusion. The novel feels more like a short story run amok and the oddball quotient is a little too high, but the combination of humor and heart is its saving grace. Author tour. (Sept.)