You may think you know all about Kate Middleton and Prince William's 2011 royal wedding, but it turns out that apart from the public pomp and pageantry, there was a late-night private celebration. In his new memoir, Meet Ella: The Dog Who Saved My Life, Princess Kate's brother, James Middleton, gives the inside story of the party.

In the book, James describes the “lively” but “calm” atmosphere of the Goring Hotel, where he stayed with his family (including the royal bride) during their April 29, 2011 wedding. While strolling through the “garden” of the property with his dog Ella, he made a rather surprising discovery: “The hotel is a place where people can relax and enjoy themselves.

“There was set up a replica of Basil's Bar on Mustique, a small private island in the Grenadines, a vacation spot the family had visited many times,” the royal sibling wrote. James described the watering hole as “the social center of the island” and noted that celebrities such as Jon Bon Jovi and Mick Jagger performed in the “modest little venue.”

“Today, a perfect replica of it has been built on the grounds of the Goring Hotel, and wedding guests can imagine themselves on the edge of the Caribbean, but actually in the middle of a London garden,” the book says.

The Middletons are regulars at Basil's Bar, which they own (oh my!). James notes that Basil was “one of the guests at the wedding.”

Hilariously, according to the Middletons, James' dog “got to visit the bar before any of the other guests. Lucky pup.

Kate's brother did not reveal any other details about the Caribbean-themed bash, but one thing we do know is that the current Princess of Wales is from her white lace Sarah Burton-for-Alexander McQueen wedding dress, to a satin ball gown for a private evening reception. Whether she had a secret third dress for the island-style party remains to be seen.

But Buckingham Palace was transformed for the lavish reception, with Ellie Goulding playing a set and guests telling The Telegraph that “there was a huge bar in the middle of the room, lots of couches for everyone to relax on when not on the dance floor, a band There was a stage for the band,” he said.

As for their hotel feast, perhaps someday the Crown Prince and Princess will show us pictures of Basil's Bar 2.0.