"Writing with the same warmth and humor that characterized her earliest novels (the Al Capsella series), Clarke introduces a new cast of endearingly eccentric characters who are drawn together to enjoy 'one whole and perfect day.' Seventeen-year-old Lily, the youngest, most 'sensible' member of the Samson clan, has well-founded misgivings about the upcoming 80th birthday party for Pop, her grandfather. She is sure something will go wrong (as it always does) when her unpredictable relatives unite, still she hopes for the 'perfect day' of the book's title. Pop himself is having a feud with Lily's shiftless brother Lonnie, and has even threatened him with an ax, causing Lonnie to leave home and move into an apartment. Pop's wife, Nan, who is as soft as Pop is gruff, might be considered normal were it not for her invisible best friend, Sef. Then there's Lily's psychologist mother, who works in an adult day-care center and is always bringing home 'old people whose care-giver children were quite desperate for a little break.' While the novel mainly focuses on Lily's exasperation with her family's peculiarities, the third-person narrative shifts among other characters' points of view, which reveal old resentments as well as their mutual affections, affections that prove to be more deep-rooted than grudges. Filled with surprising turns of events and serendipitous encounters with strangers (who ultimately take on significance in the story), this book celebrates rekindled friendship and blossoming romance. Ages 12-up. (Mar.) " Publishers Weekly (Starred Review) (Copyright Reed Business Information, Inc.)