Prince William broke the internet on Friday when he was spotted dancing away to Taylor Swift at her Eras tour concert. The future King took his two eldest children along to watch the superstar in action - and they posed for a selfie backstage with Taylor.
The candid image quickly went viral, shared on William and Kate's official social media, as well as Taylor's own account - along with a birthday message for the royal. "Happy Bday M8! London shows are off to a splendid start," she wrote.
Behavioural professional Judi James told the Mirror that the photograph is very telling - and it's clear that nine-year-old Princess Charlotte is a fully-fledged Swiftie.
"William and George wear mirrored grins here but with the angle of their heads suggesting they are shy and just a little bit in awe of Taylor," Judi noted. "Charlotte though wears a more open, symmetric and straight onto the camera grin of total delight."
Of Taylor, she added: "It's clear from Taylor's body language here that nothing fazes her. Despite just finishing her one-woman concert she looks band-box fresh here, bright-eyed and full of energy. She's also calmly leading this selfie, smiling confidently as though she poses with royals every day, as well as the current love of her life Travis."
It was a big day for William, who was also celebrating his 42nd birthday. Earlier on Friday, his wife Princess Kate released a brand new family photo to mark the occasion, and fans went wild for the fun snapshot.
The photo shows William holding hands with his three children as they jump over a sand dune - and so far it has amassed a whopping 1.7million likes. . "Happy birthday Papa, we all love you so much! Cx," read the caption.
"Happy Birthday to HRH, William, the Prince of Wales! This photo just screams pure joy and shows the love between a father and his children! An incredible photo by HRH, Catherine, the Princess of Wales!" one fan commented.
"A second added: "By far my absolute favourite shot of Prince William with his children. There is so much joy and laughter evident in this glimpse into their private family lives."
"He's had so much on his plate; it's so great to see him being carefree like this!!! Happy birthday Prince William," said a third. And a fourth concluded: "This should absolutely break the internet!! Quite possibly the best royal family picture ever!"
According to royal expert and former BBC royal correspondent Jennie Bond, the photo speaks volumes about William and Kate's enduring bond - and also their hopeful outlook.
"The last few months have been a test of their strong partnership," Jennie revealed to OK! magazine, adding, "I think this photograph tells us that they are still able to jump for joy, even in the toughest of times, and that Kate has deliberately chosen a picture that speaks of their optimism for the future.
"She adores William - he is her rock and has supported her so selflessly through all of this and has taken flak from members of the public for not doing more and for devoting himself to her. So she adores her man. I think their marriage is stronger than ever."
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