Pippa Middleton
Pippa Middleton was seen with fitness instructor James Duigan in London. Pictured: Pippa Middleton, the sister of Britain's Catherine, Duchess of Cambridge, watches the women's singles tennis match between Angelique Kerber of Germany and Heather Watson of Britain at the Wimbledon Tennis Championships, in centre court, London.Reuters

Kate Middleton's sister Pippa Middleton was spotted in a teal blue bikini during the recent family vacation at the small private island of Mustique.

The 31-year-old stunner reportedly showed off her sculpted body in a two-piece swimwear, which featured metallic ring detailing. She wore her hair loose and clutched her snorkelling gear in one hand. Pippa was reportedly seen snorkelling at one of the West Indian Island's famous beaches with her brother James Middleton.

Pippa is known for her envious figure and she reportedly follows a healthy diet to maintain it. "I've never done Dukan, attempted Atkins, or exercised religiously seven days a week, but I do believe in making healthy choices — keeping refined carbs such as white bread and pasta to a minimum, and sticking to sensible portion sizes," she wrote in a column for a British magazine, Inquisitr reports.

Pippa and James joined Kate and Prince William for the Caribbean getaway for the 60th birthday celebrations of Carole Middleton. 

Meanwhile, Kate was not seen hanging out at the beach, but was seen taking a leisurely stroll at the island with Prince George, according to NY Daily News. She was seen wearing a blue and white one-piece dress. She coupled her holiday look with a white hat and a matching bag.

Kate is currently pregnant with her second child. She will welcome the next royal child in spring. The two-week vacation reportedly serves as a babymoon for the Kate and Prince William.

After the vacation, Kate will carry out two royal engagements in Staffordshire and the West Midlands. She will be visiting two charities, including East Anglia's Children's Hospices (EACH) and Action for Children on 18 February, reports Hello Magazine. She will also visit Emma Bridgewater factory and will witness the making of earthen pottery.

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