The Royal Variety Performance aired on Sunday evening, with the Prince and Princess of Wales in attendance, alongside fellow royals Crown Princess Victoria and Prince Daniel of Sweden.
Prince William appeared to especially enjoy himself, at one point in the evening being spotted crying with laughter, as several viewers pointed out on social media!
The heir to the throne was clearly tickled by comedian Tom Allen's set, and he could be seen in hysterics, rubbing his eyes with the back of his hand and laughing before clapping enthusiastically.
Royal fans loved seeing how much fun Prince William was having
On X, one royal fan commented: "Prince William crying with laughter at Tom Allen on Royal Variety Show," adding three crying-laughing emojis. "He was absolutely loving it," another viewer agreed, while a third wrote "OK so Prince William crying with laughter at Tom Allen on the Royal Variety has made my whole night".
The star-studded event, which William and Kate attended for the first time in 2014, also featured a performance of O Holy Night by singer and Ted Lasso actress Hannah Waddingham, after which Kate could be seen animatedly chatting and appearing to compliment the star.
Also on the bill were singer and actress Beverley Knight alongside the cast of Sister Act, the Argentinian dancing troupe Malevo and a special performance from Derren Brown’s West End creation Unbelievable.
Casts of The Lion King, Frozen, Aladdin, Hercules, and Beauty & The Beast marked Disney's centenary at the Royal Variety Performance while pop rock band McFly, singer Rick Astley, pop singer Zara Larsson and singer-songwriter Paloma Faith also took to the stage.
Filmed at the end of last month, the occasion was William and Kate's first public outing since the release of Omid Scobie's controversial royal book, Endgame, but the couple appeared to be in high spirits, displaying a rare PDA and holding hands as they arrived at London's Royal Albert Hall.
Princess Kate, 41, appeared to pay tribute to the Swedish flag in a teal evening gown by Safiyaa with sweeping dramatic split sleeves.
She accessorised with statement jewellery and wore her hair in a bouncy blowdry with her fringe framing her face. Her statement dress perfectly complemented her elegant silhouette, complete with a bejewelled neckline and dramatic split sleeves.
She elevated her ritzy ensemble with matching heels, statement earrings and a sparkly clutch bag. The annual occasion, which raises money for the Royal Variety Charity, is a notoriously glamorous event that is always attended by senior royalty.
Last year, the family was represented by the Duke and Duchess of Edinburgh. Crown Princess Victoria and Prince Daniel of Sweden appeared to be enjoying being the British royals' guests of honour at this year's event, after arriving in the country for a three-day stay.
Princess Kate, 41, was seen warmly welcoming the Swedish royals with a brand new look – a sleek straight style with trendy curtain bangs. The royal also wore a stunning forest green bespoke Emilia Wickstead dress, aptly named the 'Kate'.
William and Kate's official Instagram account shared images from their meeting, with the caption: "A pleasure to welcome The Crown Princess of Sweden and Prince Daniel to Windsor this morning."
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