Celebrate? Pippa Middleton parts from her literary agent after just one book Publishers Michael Joseph (part of Penguin) won a fierce bidding war for Pippa Middleton's first book, Celebrate, and are believed to be planning two follow-ups. However, the younger sister to the Duchess of Cambridge has parted ways with the literary agent who negotiated her publishing deal (and a reported £400,000 advance) after just one book. Following weeks of speculation after the desultory sales performance of Pippa's party tips tome, agent Richard Godwin today confirmed she was no longer on his books. I am very sorry it has happened but it is true. I no longer represent Pippa and I wish her every good luck," Godwin, a highly respected agent, Godwin also represents Vikram Seth, Claire Tomalin and William Dalrymple, said. Celebrate, the 29-year-old's collection of "personal tips, favourite recipes and useful decorating ideas," was published in November to calls of derision from the critics who mocked its banality. In its first week sales of the 416-page guide were slow, with just 2,189 copies of the title sold, making it only the 185th bestselling book of the week - and unlikely to help Penguin reap back its advance fee. "[Richard Godwin and Pippa had] a tricky relationship," an unnamed literary figure quoted in the Daily Mail said. David was not an obvious choice for Pippa. His writers are heavyweights while Pippa's niche is fluffy and commercial. In the end it was clear the union was not a happy one. Despite Celebrate's lack of commercial success Pippa has already secured her next writing job as a columnist for Waitrose magazine.