Prince William celebrated his 42nd birthday with Taylor Swift at Wembley Stadium along with his children.
The future King also broke a longstanding Royal rule, "no selfies" by sharing a photograph with Swift, Char and George.
Swift, 34, was welcomed to London by the royal guard earlier on June 21 when the band played "Shake It Off" in front of Buckingham Palace.
"Can’t stop, won’t stop groovin’," the royal family captioned a video of the performance on social media.
Other famous fans on hand, Sir Paul McCartney, Tom Cruise, Ashton Kutcher, Mila Kunis and Jon Bon Jovi.
Also, Tay's boo Travis Kelce joined her on stage in London and nailed the choreography as he picked her up and carried the tortured poet.