Prince George and Princess Charlotte adorably cheer on their parents at the King's Cup Regatta

Prince George and Princess Charlotte cheered on their parents, the Duke and Duchess of Cambridge, at the inaugural King's Cup Regatta on Thursday, Aug. 8 in Cowes, England on the Isle of Wight. The two looked absolutely adorable watching from a boat deck with their grandparents, Michael and Carole Middleton. Although, we couldn't help but notice that George seems to have hit a major milestone since the last time we saw him.

Most notably, the future king was missing his two front teeth! The 6-year-old prince smiled with what teeth he did have, however, wearing a boat captain's hat with a nautical-looking navy and white striped polo shirt and black life jacket.

Princess Charlotte wore a blue and white striped dress with her life jacket, watching mostly from inside the boat.

The last time the siblings were spotted in public was at a charity polo match with their mother, Kate Middleton, and brother, Prince Louis, as well as their aunt, Meghan Markle, and new cousin, Archie Harrison. In photos captured at the event, George seemed to have all of his top front teeth, as well as in photos released for his sixth birthday on July 22.

For his big day, the Cambridge family traveled to Mustique for their annual summer holiday and stayed in a lavish villa with bunk beds for George and his siblings. The family also visited the private Caribbean island for his fifth birthday and it was reported that George learned to swim. He's growing up so fast, perhaps we'll see him sailing in the regatta in a few years!

Prince William and Kate Middleton launched the King's Cup Regatta this year to raise funds and bring awareness to eight royal-supported charities. The duke and duchess played skipper on two boats, while six others, each representing a different charity, were led by celebrity ambassadors like Bear Grylls and English footballer Fara Williams. Fans were invited to watch the race and prize ceremony for free from the SailGP Race Village, which included a 500-seat grandstand for optimal viewing.

In the first race, Grylls came in first place while representing Prince William's cause, Tusk. The Duke of Cambridge came in third place with Child Bereavement UK and the duchess came in seventh, representing The Royal Foundation.

The regatta was originally slated to take place on Friday, Aug. 9, but had to be moved up due to severe weather warnings.