Prince William, Prince of Wales with his children Princess Charlotte, Prince Louis and Prince George (Picture: Millie Pilkington/Kensington Palace via Getty Images)

The Prince of Wales has been pictured smiling with his three children in a photo released by Kensington Palace to mark Father’s Day.

The photograph shows Princess Charlotte and Prince George on either side of their father, smiling up at him, with the youngest sibling Prince Louis hugging William on his shoulders from behind.

The children and their father are all dressed in blue, with George, nine, and William, 40, both in trousers and casual shirts.

Louis, five, is his typically excitable self and is beaming in a blue jumper, while his brother and sister appear more relaxed.

Charlotte, who turned eight last month, is dressed in a blue flower print dress and white cardigan and has a tooth missing in her smile.

The picture was taken on the Windsor estate earlier this year by Millie Pilkington, who has photographed the Prince and Princess of Wales’s children on a number of occasions.

All five members of the family were involved in Saturday’s Trooping the Colour, the first of King Charles’ reign.

Louis, on the Buckingham Palace balcony, saluted during the traditional Trooping flypast and also pretended to ride a bike with his arms stretched out.

They were all pictured together at the Trooping flypast (Picture: AFP via Getty Images)

The Princess of Wales joined her children in a carriage with the Queen, travelling just behind the King, who was on horseback as part of the procession in a return to a tradition that Queen Elizabeth II stepped back from more than thirty years ago.

William rode behind his father, alongside the Duke of Edinburgh and the Princess Royal.

Camilla and Catherine, as royal colonels, had prominent roles in the Trooping.

Catherine wore an eye-catching green dress and hat, alluding to her role as Colonel of the Irish Guards.

The Queen wore a red dress and black beret to represent her position as Colonel of the Grenadier Guards.

The picture has been taken on the Windsor grounds.