The Prince and Princess of Wales have shared a public message to King Charles.
In honour of the monarch's 78th birthday, the future King and Queen took to their joint Instagram account to celebrate His Majesty.
"Wishing a very Happy Birthday to His Majesty The King!" the couple penned, sharing the message alongside a recent photo of Charles and Elton John.
The image was taken of the duo as they joined forces to record an hour-long special episode of Sir Elton's Apple Radio show Rocket Hour, which will air this evening in honour of Charles' birthday.
The top-secret recording took place last month, when both men visited Apple Music Studios at Battersea Power Station, and was designed to highlight the close connection of music to the work of the King's Trust, which turns 50 this year.
Why does King Charles have two birthdays?
While Saturday marks the King's 'real' birthday, he also has an 'official birthday' in the British calendar.
This is due to a royal tradition designed to ensure good British weather for outdoor public celebrations.
Because his actual birthday falls in mid-November – when London weather is typically cold, rainy, and unpredictable – his official public birthday is ...