The tennis-loving family attended the Wimbledon men's final, watching Novak Djokovic defeat Nick Kyrgios to win his seventh Wimbledon championship.
George, the oldest of William and Kate's three children, sat in between his parents in the royal box in his first public appearance at the Grand Slam tournament.
Though George appeared enthralled by the four-set match between Kyrgios and Djokovic, his favorite player is eight-time Wimbledon winner Roger Federer, according to Kate.
The duchess said in a 2019 interview the tennis star has even played tennis with George.
She presented the championship trophy to Djokovic after Sunday's match. A video shared by the official Wimbledon Twitter account showed George meeting Djokovic after the match and holding the trophy himself.