Prince William shares moving tribute to Prince Philip with photo of his late grandfather and Prince George

By Heather Cichowski, with files from Zach Harper

Prince William has paid tribute to his late grandfather Prince Philip in a moving message, which was shared on the Kensington Royal Instagram and Twitter. The emotional note also included a never-before-seen photo of the Duke of Edinburgh with William and Kate's eldest son, Prince George.

"My grandfather’s century of life was defined by service – to his country and Commonwealth, to his wife and Queen, and to our family," William began his tribute, which was shared on April 12. Philip passed away at the age of 99 on April 9.

"I feel lucky to have not just had his example to guide me, but his enduring presence well into my own adult life – both through good times and the hardest days," he continued.

William also reflected on the time Philip was able to spend with wife Kate and their children George, Princess Charlotte and Prince Louis.

"I will always be grateful that my wife had so many years to get to know my grandfather and for the kindness he showed her," the Duke of Cambridge penned. "I will never take for granted the special memories my children will always have of their great-grandpa coming to collect them in his carriage and seeing for themselves his infectious sense of adventure as well as his mischievous sense of humour!

"My grandfather was an extraordinary man and part of an extraordinary generation," he said in closing. "Catherine and I will continue to do what he would have wanted and will support The Queen in the years ahead. I will miss my Grandpa, but I know he would want us to get on with the job."

MORE: Prince Harry arrives back in the United Kingdom ahead of the funeral of grandfather Prince Philip: reports

The accompanying photo shows the Duke of Edinburgh in his carriage with George sitting next to him. Philip is wearing a navy jacket and George is clad in a blue sweater and shorts with a navy polo and navy socks. The image captures the pair's similarities as they both grin. The image was taken by the Duchess of Cambridge, although it is not known when. George looks like he could be about four or five years old in the image.

Royals fans got to see Prince Philip with his grandchildren and great-grandchildren at 2017 Trooping the Colour, including Kate and William's children, Prince George and Princess Charlotte. Photo: © James Devaney/WireImage

William's tribute comes after Philip's children and other members of the Royal Family have started to publicly pay tribute to the Queen's beloved husband of more than 73 years.

Princess Anne opened up about the death of her father and thanked fans for the support in a statement shared on April 11.

"I regard it as an honour and a privilege to have been asked to follow in his footsteps and it has been a pleasure to have kept him in touch with their activities," the Princess Royal said regarding the duke's work. "I know how much he meant to them, in the UK, across the Commonwealth and in the wider world."

Prince Charles, Philip and the Queen's eldest child and the heir presumptive, made a touching statement about his "dear Papa" via video from Highgrove House.

On April 11, Prince Edward, the Countess of Wessex, Lady Louise Windsor and Prince Andrew all stepped out to a church service in Windsor and thanked the public and royal workers for their support during this difficult time. Edward, who is the Queen and Philip's youngest child, said his father's death had been very difficult to process.

A pre-recorded message from Edward and Anne talking about their father's legacy was also released following Phillip's death.

William was originally going to participate in the 2021 BAFTAs on April 10, as part of his role as president, but withdrew from his appearance in light of Philip's passing.

The Duke of Edinburgh is set to receive a ceremonial royal funeral service on April 17, at St George's Chapel, Windsor Castle but the event has restrictions in place due to the coronavirus pandemic. Prince Harry reportedly arrived in London after flying in from California on April 11 and is now quarantining.

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