The Duke and Duchess of Sussex have posted a new photo of baby Archie on Instagram as a birthday tribute to Prince Charles.
The royal couple shared the black and white photo showing three generations of the royal family, including the latest member Archie Harrison Mountbatten-Windsor.
Prince Harry is seen holding his son, who is wearing a white lace christening gown while his grandfather Charles looks on.
The Duke and Duchess wrote the caption: "Happy birthday to His Royal Highness The Prince of Wales - Sir, Pa, Grandpa!"
The picture racked up more than 60,000 likes in just 15 minutes, with David Beckham and journalist Bryony Gordon showing their support.
The Cambridges also sent Charles a birthday message on their official social media accounts, posting a touching image of him with Prince Louis.
The heir to the throne is seen holding Louis' hands as the royal youngster is in Kate's arms. The photo was part of a series taken to mark Charles's milestone 70th last year.
The message read: "Wishing a very happy birthday to The Prince of Wales!".
It was also accompanied by a photo of Charles and William, and another of Charles, William and Harry, in military dress, laughing together.
The Royal Family's Twitter account posted "Wishing The Prince of Wales a very happy birthday!".
It included a photo of a young Duke of Edinburgh holding his baby son Charles in the air.
It comes as Prince Charles celebrates his 71st birthday today - which will make him the oldest monarch to ever take the thrown after William IV, who was crowed at age 64 in 1830.
He is celebrating his birthday at a small event in Mumbai, attended by local schoolchildren, whose education is supported by his charitable foundation, the British Asian Trust.
The schoolchildren presented the royal with a present featuring the stories of Hindi deity Krishna, sung "Happy Birthday" and gave him a chocolate cake.
True to tradition, BBC Radio 4 played the national anthem in tribute to a royal family member's birthday.
