Kate Middleton's Birthday Photo, Message For Prince William Hint At Massive Royal Change, Expert Claims

Kate Middleton paid a sweet tribute to her husband, Prince William, on his birthday, and it seemed to have hinted at a massive change in the royal household, according to an expert.

The Princess of Wales shared a fun family photo on her and Prince William's official social media accounts on X and Instagram. In the snap, the father of three and his kids -- Prince George, 10, Princess Charlotte, 9, and Prince Louis, 6-- are holding hands while jumping in the air. It was taken by Middleton when she was in Norfolk last month, per the Mirror.

"Happy birthday Papa, we all love you so much! Cx," Middleton wrote in the caption.

Dr. Tessa Dunlop, a royal expert and historian, weighed in on Middleton's birthday tribute for her husband. According to her, it hinted at a massive royal change, especially in terms of what the family had gone through in the past months, and the "winsome photograph speaks to how far the family has come." Both King Charles and the Princess of Wales were diagnosed with cancer earlier this year.

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"The children's love and trust is framed in the shot -- a leap of faith alongside their father. And the princess doubles down on that sentiment through her unequivocal messaging. 'Happy Birthday Papa, we all love you so much! Cx'. George, Charlotte and Louis love their Dad 'so much!' As does Kate," Dunlop explained to the Mirror.

"The inclusive 'we all' phrasing accompanied by her hallmark sign off, 'Cx' implicates the Princess of Wales in this close-knit unit. Here is a family who have faced down adversity and come through it stronger and more united."

Dunlop acknowledged that others would probably question the significance of the photo. However, the expert said it was a big deal, considering what they went through.

Aside from the health scare, there were allegations of disunity and the family's infamous falling-out with the Sussexes. Additionally, Middleton was accused of Photoshopping her Mother's Day photo. However, the recent photo featured a deep meaning.

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"They are jumping for their mother, and she is catching them as they fall," Dunlop continued.

"Best of all, photographer Kate has put her husband William in the parenting spotlight. Casually dressed, arm-in-arm, holding hands, larking with his children, this version of the Prince of Wales has an unexpectedly contemporary vibe. Above all else he is a doting father and husband, doing his best, and they love him for that."

Middleton's birthday photo received a thumbs-up from several online users. Many even said it was probably the best portrait they had ever seen.

"Possibly the best picture I've seen of the family," The Big Ladder Photographer commented on Instagram.

Another social media user added, "The best bday photo I've seen. Happy Bday Prince William!"

"What a capture !!" someone else said.