Pippa Middleton Opens Up About Her Slim Fitting Royal Wedding Dress

Kate's sister addresses how it fit her "backside."

Feb. 26, 2014 — -- When Pippa Middleton wore "that dress" to the Royal Wedding three years ago, it created an overnight fashion sensation.

And at the Women in Advertising and Communications dinner in London last night, Middleton admitted she remembers it well.

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"As I have found out, recognition has its upside, its downside, and -- you may say -- its backside," she told the crowd, Glamour reports.

The Duchess of Cambridge's younger sister, 30, added, "In retrospect, it fitted a little too well," she said of the dress designed by Alexander McQueen designer Sarah Burton.

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She added that she was so nervous for her sister's wedding to Prince William that she didn't sleep for a couple nights before.