WATCH: Prince George celebrates his 5th birthday: Look back at his most adorable moments
Prince George, the heir to the British throne and the oldest child of Prince William and Princess Kate, is celebrating his fifth birthday Sunday.
George is spending his birthday week in Mustique on a family vacation that includes not only his parents and siblings, Princess Charlotte and Prince Louis, but also his aunt and uncle, James and Pippa Matthews, and his maternal grandparents, Michael and Carole Middleton.
On Saturday, Kensington Palace shared a picture on Twitter of a beaming Prince George to mark his birthday and thanked "everyone for your lovely messages."
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In this photo taken July 9, 2018, Britain's Prince George poses for a picture following the christening of his brother Prince Louis, at Clarence House in London. Britain's Prince William and Kate, Duchess of Cambridge have released a photo of Prince George to mark his fifth birthday on Sunday, July 22.
The photograph was taken in the garden at Clarence House by Matt Porteous, following the christening of Prince Louis on July 9.
“The Duke and Duchess of Cambridge are very pleased to share a new photograph of Prince George to mark His Royal Highness's fifth birthday tomorrow.” Kensington Palace said in a statement
When George was born at St. Mary's Hospital in 2013, his birth caused a media frenzy around the world and in the U.K., where Brits celebrated the birth of their new heir.
To mark George's birthday, the Royal Mint has issued a £5 (around $6.50) commemorative coin, which is available to the public for purchase, features an image of St. George, the patron saint of England, and a dragon.
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A handout photo made available by the British Royal Mint showing the back side of the new five GBP coin in celebration of His Royal Highness Prince George's fifth birthday, July 22, 2018.
Now a student at St. Thomas's Battersea School in London, George has had a busy few months with the royal family.
He was a page boy at the May 19 wedding of his uncle, Prince Harry, to Meghan Markle, attended Louis' christening, and made an appearance with the royal family at Trooping the Colour.
AP
Britain's Prince George leaves after the wedding of Prince Harry and Meghan Markle at St. George's Chapel in Windsor Castle in Windsor, May 19, 2018.
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Duchess of Cambridge, Kate and Britain's Prince William with their children Prince George, Princess Charlotte and Prince Louis as they arrive for Prince Louis' christening service at the Chapel Royal, St James's Palace, London, July 9, 2018.
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Princess Charlotte, Savannah Phillips and Prince George on the balcony of Buckingham Palace after Trooping the Color in London, June 9, 2018.
Take a look back at some of George’s most adorable moments through the years.
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Prince William, Duke of Cambridge and Catherine, Duchess of Cambridge, depart The Lindo Wing with their newborn son, Prince George, at St Mary's Hospital on July 23, 2013 in London.
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Prince William and his wife Catherine, Duchess of Cambridge, arrive with their son Prince George at Chapel Royal in St James's Palace in central London, Oct. 23, 2013, ahead of the christening of the three month-old prince.
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Prince William, Duke of Cambridge, Catherine, Duchess of Cambridge and Prince George of Cambridge meet a Bilby called George as they visit the Bilby Enclosure at Taronga Zoo on April 20, 2014 in Sydney.
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Britain's Prince William and his son Prince George wave as they return to St. Mary's Hospital's exclusive Lindo Wing, London, May 2, 2015.
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Catherine, Duchess of Cambridge, Prince William, Duke of Cambridge, Princess Charlotte of Cambridge and Prince George of Cambridge, Queen Elizabeth II and Prince George's nanny, Maria Teresa Turrion Borrallo leave the Church of St Mary Magdalene on the Sandringham Estate for the Christening of Princess Charlotte of Cambridge on July 5, 2015, in King's Lynn, England.
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Prince George is seen on his way to his first day of nursery school, Jan. 6, 2016.
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President Barack Obama and First Lady Michelle Obama meet Prince George, while the Duke and Duchess of Cambridge watch, at Kensington Palace in London, April 22, 2016.
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Prince George of Cambridge reacts as the royals view helicopter models before departing from Hamburg airport on the last day of their official visit to Poland and Germany on July 21, 2017, in Hamburg, Germany.
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Britain's Prince William accompanies Prince George as he is met by Helen Haslem - the head of the lower school on arrival for his first day of school at Thomas's school in Battersea, London, Sept. 7, 2017.
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Prince George of Cambridge attends the Maserati Royal Charity Polo Trophy at the Beaufort Polo Club on June 10, 2018, in Gloucester, England.
