Prince William and Kate Middleton dancing on trip

The Duke and Duchess of Cambridge were able to enjoy some special alone time during their family holiday in Mustique last week. The couple, who have three children under the age of five, were spotted on a rare and casual night out at the island's famous Basil's Bar. The theme of the bash, which was also attended by Mick Jagger and his daughter Jade, was a "Splash of Gold". Fellow revellers have exclusively revealed to our sister magazine HELLO! that William and Kate were spotted "on the early side" of the evening and looked to be having a great time. Sources also filled us in on the famous pair's style, saying they were "island chic". 

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Prince William and Kate Middleton are on summer holiday Photo: Getty Images

Prince William fittingly sported a Pink House Mustique butt-down shirt for the outing, supporting the brand which is British-designed, but inspired by the island. "They were there for the cocktails segment and kept it rather classy," the source elaborated. It's important to note that the royal couple are good friends with legendary barman Basil Charles of Basil's Bar. He even set up a pop-up bar at The Goring hotel in London, where Kate stayed the night before her wedding, during the week of the nuptials in 2011.

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Prince William rocked a Pinkhouse Mustique shirt for the fun night out Photo: Pink House Mustique

The Duke and Duchess, both 36, have been enjoying a much-deserved holiday on the private Caribbean island for the past couple of weeks. They are thought to have joined Kate's parents Carole and Michael Middleton on the Middletons' annual break. It could very well have been the doting grandparents who stayed home with Prince George, Princess Charlotte and Prince Louis while William and Kate had a night off parenting duties at the beach-side establishment.

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The Cambridges have been enjoying their first holiday as a family of five Photo: Getty Images

The royals first visited Mustique in 2008 and have been returning ever since. This time around is the Cambridges' first holiday as a family of five. Prince Louis was born back in April, joining his big brother Prince George, who turned five on July 22 while the family was in Mustique, and Princess Charlotte, who turned three this past May.

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Given the complete privacy of the exclusive island, it comes as no surprise that William and Kate let their hair down and blend in with other tourists. With a no-fly zone enforced over Mustique and the discretion of other guests, the royals are able to truly relax and be themselves. On previous trips, William and Kate have played tennis, gone snorkelling and scuba diving, and enjoyed cocktails at the five-star Cotton House resort.

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