The Duke of Cambridge has released a personal message in honour of his 40th birthday on Tuesday.
Taking to Kensington Palace's official Twitter account, Prince William thanked royal well-wishers for the congratulations he received on his special milestone. He wrote: "Thank you for all the happy birthday messages today! W."
WATCH: A look at the Duke of Cambridge at 40
His milestone birthday comes in the Queen's Platinum Jubilee year and, mirroring his grandmother's commitment to duty and service, he has vowed to continue to raise the issue of homelessness in an article for the Big Issue.
Earlier this month, William joined vendor Dave Martin, 60, to sell copies of the magazine on the streets of west London. In the special issue, he penned: "I was 11 when I first visited a homeless shelter with my mother, who in her own inimitable style was determined to shine a light on an overlooked, misunderstood problem."
The Duke continued: "I wanted to experience the other side and see what it was like to be a Big Issue vendor. My time was truly eye-opening.
Prince William has vowed to continue to raise the issue of homelessness
"I have always believed in using my platform to help tell those stories and to bring attention and action to those who are struggling.
"I plan to do that now I'm turning 40, even more than I have in the past. So, for my part, I commit to continue doing what I can to shine a spotlight on this solvable issue not just today, but in the months and years to come."
He added: "And in the years ahead, I hope to bring George, Charlotte and Louis to see the fantastic organisations doing inspiring work to support those most in need – just as my mother did for me."
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