The Duchess of Cambridge received thousands of well wishes from people around the world on her 40th birthday, but there was one message shared that was particularly touching.
Mila Sneddon was among those to post a birthday message for Kate. In a video shared by her mother, Lynda, on Twitter, she said: "Happy Birthday Catherine! I'm so happy you're turning 40, hope you get a nice gift and love spending time with your family. Bye, lots of love, Mila."
And the Duchess took the time to reply from @KensingtonRoyal's official social media account, writing: "Thank you Mila!"
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The six-year-old captured Kate's heart after a photograph of the little girl was included as part of the royal's Hold Still project in 2020.
Mila, who is undergoing chemotherapy for leukaemia, was pictured kissing her home's kitchen window after being separated from her father during the first lockdown.
Kate responded to the video message from Mila
The Duchess first spoke to Mila over a Zoom call in autumn 2020, promising the youngster that she would wear a pink dress when they could meet in person.
True to her word, Kate wore a bubblegum pink Me+Em dress as the pair met face-to-face at the Palace of Holyroodhouse in Edinburgh in May 2021.
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The Duchess was reunited with Mila at her Christmas concert
Mila and her family were also invited to the Duchess' Christmas carol concert at Westminster Abbey in December. The little girl, who gave a short reading, was seated behind the royals at the festive event and said of Kate: "She asked me what I was getting from Father Christmas and I told her I wanted a Barbie Dreamhouse. I showed her my dress and she said I looked lovely."
Kensington Palace shared three new portraits of the Duchess, taken by Paolo Roversi, ahead of her milestone birthday. Kate stunned in gowns made by her wedding dress designer, Alexander McQueen, as well as jewellery owned by the Queen and the late Princess Diana.
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