The title manifests the theme of this agreeable family portrait: Andy, 15, relays events between Grams' breaking her arm and, consequently, having to squeeze into her son's cramped San Francisco house with his unwilling wife and five kids, and her elopement, months later -- assisted by her three teenage grandchildren -- with a gentleman whose daughter is as horrified by the match as Grams' son is. Meanwhile, adjustments are made, characters revealed, and family alliances rearranged. Ma, who's always been riled by Grams' lack of tact, sympathetically supports her right to self-determination, as do Andy's sisters Dennie (17) and Molly (13); Pop, who feels threatened by any change, is stereotypically protective of his mother. Other narrative threads reinforce the theme while dispelling characters' misconceptions about one another: Ma's new job shifts some responsibility for the six-year-old twins onto the teenagers, with humorous results; Pop dislikes Dennie's boyfriend as well as Grams's; a reluctant Andy is pushed into a first date, doubling with his best friend and Molly. As narrator, Andy is a curiously effective choice, an oblivious teen not quite ready to respond sensitively to others. Filtering the story through his eyes gives it an interesting dimension, though Andy himself isn't revealed beyond his family concerns -- not usually paramount for a boy his age. Even so, Derby's genuine insights into this typically idiosyncratic family, and the engaging, kid-engineered elopement sequence, make this third novel her best yet.