Following tradition, the card sent featured a photo of the young royal with a note on the back. Proud parents Kate Middleton and Prince William chose a smiling (yet toothless!) photo of their eldest son sporting an official England National Soccer Team jersey, released for his birthday along with two other shots.
“The Duke and Duchess of Cambridge appreciated your kind thought in writing to Prince George on the occasion of his sixth birthday,” read the message, according to royal fan loopycrown3. “This was most thoughtful of you and greatly appreciated by Their Royal Highnesses who send you their best wishes.”
Kate was behind the camera to capture the adorable shot of Prince George, along with another photo of the future king laughing in the grass. A third snap was taken during the family’s vacation to the private Caribbean island of Mustique.
The images were more intimate than George’s past official birthday photos, as the family often taps professionals when it comes time for the prince’s annual snaps. (Kate has shot official birthday portraits for Princess Charlotte and Prince Louis.)
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During a visit to a center that supports young first-time parents and children in London last month, the royal mom of three opened up about her own family.
“She said children grow up so quickly and she can’t believe that George is six already,” Chloe Koroma, 23, said after chatting with Kate.
Prince George celebrated his sixth birthday on July 22 with his family on the private island of Mustique — a royal family favorite.
“He’s a jolly little person and inquisitive,” a family friend previously told PEOPLE.