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Her sister, The Duchess of Cambridge, may have adjusted to the royal spotlight effortlessly, but for Pippa Middleton, dealing with fame hasn't come so easy.

Promoting her new party planning book, Celebrate, typically tight-lipped Pippa Middleton, 29, opens up for the first time to the U.K.'s Mail on Sunday about the difficulties of being thrust into the spotlight after her sister, Kate Middleton, 31, married Prince William, 31, in April 2011..

"It is a bit startling to achieve global recognition before the age of 30 on account of your sister, your brother-in-law and your bottom," Pippa said. "One day I might be able to make sense of this. In the meantime I think it's fair to say that it has its upside and its downside."

images courtesy of the Daily Mail

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Pippa added, "I certainly have opportunities many can only dream of – but in most ways I'm a typical girl in her 20s trying to forge a career and represent herself in what can sometimes seem rather strange circumstances."

"I am by nature an optimist so I tend to concentrate on the advantages," she adds. "One of the most attractive has been the chance to publish Celebrate."

image courtesy of Viking

Middleton also says she hopes her book will give the public an inside look into who she is and what she does for a living. "I know many of you will pick up the book out of nothing more than curiosity," she writes in Celebrate.

"I can assure you that it feels even stranger to me than it probably does to you to have seen so much written about me when I have done so little to paint a picture of myself."

"This is my first chance to do that and I've enjoyed every minute of it," she writes. "The book is designed to be a comprehensive guide to home entertaining, based on my experience in my family's business Party Pieces and work for London-based events company Table Talk."

Viking will publish the 400-page guide on Oct. 30 for a retail price of $50.

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