Credit: Jonathan Pow / rossparry

Pippa can't be perfect all the time.

Pippa Middleton turned up at the country wedding of her college chum Humphrey Bowles in the North Yorkshire hamlet of Lythe on Saturday. But this time, Duchess Kate's little sister didn't wow with her nuptial couture.

Pippa, 28, wore a clingy, knee-length silk green Suzannah dress and a black feather fascinator plus strappy suede high-heel pumps.

The problem? Green has long been considered bad luck to wear to wedding ceremonies -- according to the adage "weddings and green should never be seen." (As the royal wedding maid of honor April 29, Pippa wore green at the reception -- not the ceremony -- dazzing in a plunging, emerald-toned Alice Temperley gown.) Her other faux pas was her footwear: Britain's Daily Mail points out that high heels are considered inappropriate for country weddings.

Middleton was without her beau Alex Loudon at the Bowles wedding, which took place at St. Oswald's Church. (Middleton and Bowles attended the University of Edinburgh together; the bride was Hattie Dawson.) Instead, she attended the nuptials with her parents Michael and Carole Middleton plus kid brother James.

It's the fifth wedding of 2011 for Middleton -- including, of course, her sister Kate's historic, royal day with Prince William on April 29.

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