pippa middleton
Pippa Middelton, sister of the bride Kate Middleton arrives to the wedding of Britain's Prince William and Kate Middleton in central London April 29, 2011. Reuters

Kate Middleton’s sister Pippa almost upstaged the duchess’s wedding at Westminster Abbey on April 29, 2011, thanks to her fabulous bridesmaid dress and now-famous posterior. But now she’s saying the gown that helped make her a star might have fit a little too well after she found herself gracing the covers of tabloids and even various Internet memes.

During a London dinner for the group Women in Advertising and Communications Tuesday night, Middleton revisited her much-discussed maid of honor dress at the royal wedding. "As I have found out, recognition has its upside, its downside, and — you may say — its backside," Middleton joked, according to E! Online, referring to wearing the ivory Alexander McQueen dress she wore to Kate and William's nuptials.

The future queen's younger sister, now 30, explained she was “glad it fitted” her at the time of the wedding, but after it turned her into a sensation, she added "in retrospect, it fitted a little too well."

But her backside wasn’t the only thing Middleton discussed at the dinner. Apparently she was really candid about being disappointed over her party planning book “Celebrate” not selling well. It reportedly sold a mere 18,000 copies.

"She talked about the royal wedding and her career since," a source told The Mirror. "She came across as really grateful for the opportunities but also talked about the pitfalls of her position."

Middleton finds it strange to deal with the success her derriere has received. In 2012 she told the Mail on Sunday: "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," she 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."

Some have even gone as far as accusing her of having extra support underneath her gown. "I'm not convinced that it's completely natural," London spa owner Lesley Reynolds Kahn said of Pippa's appearance in a TLC special called “Crazy About Pippa.”

"Because I think, if you look at other photos of her and you see her in jeans, she's got quite a flat bottom. I think possibly for the day, for that gorgeous dress, she may have had some sort of pants that gave her a little bit of a lift, or even a little bit of padding."

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