Taking to the comment section on social media, throngs of fans exclaimed just how similar Prince George and Prince William are.
"Handsome boy. Looks like his daddy," wrote one fan.
While another commented: "Wow, he looks exactly like his dad! Happy sixth birthday, Prince George!"
Currently holidaying on the private Caribbean island of Mustique to celebrate the future King of England's special day, the Duke and Duchess of Cambridge released adorable new photos of their very grown-up looking son for the occasion.
To accompany the happy snaps of Prince George, Kensington Palace wrote:
"The Duke and Duchess of Cambridge are very pleased to share three new photographs of Prince George to mark His Royal Highness's sixth birthday," read a statement shared by Kensington Palace.
"Two photographs were taken recently in the garden of their home at Kensington Palace, and the other was taken while on holiday with the family. All were taken by the Duchess of Cambridge."