Prince William, Prince George, Princess Charlotte, Prince Louis attend London Eras Tour

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Prince William and his three children spent his birthday joining in on the Swiftie fun.

On Friday, Prince William and his kids, Prince George, Princess Charlotte and Prince Louis, attended night one of Taylor Swift’s London Eras Tour, ABC News understands.

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The news comes hours after a sweet photo by William’s wife, Princess Kate, was shared on Instagram on Friday on the Prince and Princess of Wales’ official Instagram post for Prince William’s birthday featuring William and his three kids jumping in the air.

Prince William’s and Swift’s friendship goes way back.

In 2013, the two took the stage at a London fundraising gala with Jon Bon Jovi where they belted out “Livin’ On a Prayer.”

Prince William opened up about the moment in 2021 during an episode of Apple Fitness+’s “Time to Walk,” an audio fitness experience in which a guest host walked listeners through a location that is meaningful to them.

“To this day, I still do not know what came over me,” Prince William said at the time about his moment on stage with Swift and Bon Jovi. “Honestly, even now I’m cringing at what happened next, and I don’t understand why I gave in. But frankly, if Taylor Swift looks you in the eye, touches your arm, and says, ‘Come with me…’ I got up like a puppy and went, ‘Yeah, OK, that seems like a great idea. I’ll follow you.”

Taylor Swift kicked off her London tour stop at Wembley Stadium on Friday night.

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During her first show in London, photos show that Swift performed her “Fearless” set in a black and gold fringe dress. She also wore an oversized, black, pinstriped blazer with her iconic over-the-knee boots, which she typically wears for her “Lover” set.

The singer is slated to deliver two more shows there with Paramore, Mette and Griff as her opening acts, before taking over Aviva Stadium in Dublin, Ireland, next weekend.

See photos from her night one of her London Eras Tour below.