Prince William and Kate Middleton released the black-and-white photo on the prince's 11th birthday on Monday.
The Princess of Wales marked her first official return to public engagements this year when she attended a military parade in June.
The new photo comes just one day after the Princess of Wales made her first public appearance in six months.
The young royal couldn't help but get funky as he listened to bagpipe music at Trooping the Colour in London.
The Princess of Wales attended Trooping the Colour on Saturday, and made a very special appearance alongside her three children.
The Princess of Wales joined other members of the royal family on a Buckingham Palace balcony at the end of the King’s Birthday Parade.
The Princess of Wales has not attended a public engagement since December 2023.
It’s the first time the Princess of Wales has publicly provided a health update since announcing her diagnosis in March.
The Princess of Wales, who has been recovering from cancer, told the Irish Guards she was "very sorry" to miss the rehearsal before the Trooping of the Color parade.
The Princess of Wales revealed on March 22 that she had been diagnosed with an unspecified kind of cancer.
