[09:38] Pippa Middleton, sister of Catherine, Duchess of Cambridge, poses for photographers to promote her first book
Pippa Middleton, sister of Catherine, Duchess of Cambridge, poses for photographers to promote her first book "Celebrate", on the subject of party planning, in London October 25, 2012. Reuters/Neil Hall

Pippa Middleton looked stunning in a blue gown at the Boodles Boxing Ball in London on Saturday. The younger sister of the Duchess of Cambridge, Kate Middleton, flaunted her toned body in a vibrant blue confection at the annual event hosted by celebrity chef Gordon Ramsay.

Pippa’s gown featured a halter neck with a bandeau-style bust, which was adorned with an embellished flower appliqué and had a cut-out near the midriff. The high-low style number was cinched at the waist and also exposed a part of her back.

Kate’s sister accessorised with a pair of metallic grey T-strap high heeled sandals and a blue jewel-embellished clutch as she attended the annual charity event in aid of the Gordon Ramsay Foundation at the Grosvenor House Hotel, People reported. She wore her long brunette tresses loose, styled in waves. Pippa wore no make-up for the bash.

Middleton arrived at the event with a group of friends, including Tom Kingston. Her brother-in-law Prince William’s friend Hugh van Cutsem was also in attendance at the annual charity.

Meanwhile, the host and hostess of the party Ramsay and his wife Tana Ramsay channelled elegance in their respective looks. The celebrity chef looked dapper in a blue suit, paired with a crisp white shirt and black tie. He finished his look with black lace-up boots.

His wife complimented him in a black sleeveless dress, with a plunging neckline and sexy cut-out detail . Tana wore her brunette tresses in curls with a middle part. She accessorised with a small chain and sleek bracelet. Her make-up included glossy lips, pink manicure and black eyeliner.

In earlier years, Prince Harry, Prince William and Kate Middleton have attended the Boodles Boxing Ball . But, this year Pippa was the only person from the extended family to be in attendance.

Earlier, the brunette beauty, who turned 32 last week, competed in a gruelling 47-mile swim-run competition in Sweden on Sept. 7 and postponed her birthday celebrations for a later date.

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