Charlotte donned sunglasses and ran in bare feet, at one point attempting a head stand in front of her laughing mom.
The fun-loving princess has been showing off her playful side recently, waving to crowds while meeting her baby brother Prince Louis at the Lindo wing, and while fulfilling her bridesmaid duties during uncle Prince Harry's wedding to Meghan Markle.
George, who turns 5 in July, watched the match alongside Kate and showed her a slinky toy.
While other royal family members such as the Duke and Duchess of Cambridge and the Duke and Duchess of Sussex share information through Kensington Palace's Instagram and Twitter accounts, Princess Eugenie is free to post away to her 207,000 followers. My American side here, biased maybe b/c of everyday gunviolence in US, but my British side agrees.More news: Michael Cohen expected to flip as attorneys leave case
"In this context - a public event that invites the public to participate - it's risky to allow a toy gun, because many people look to the family for compassion and leadership", Gilboa tells Yahoo Lifestyle. "Lucky George isn't black or police would have shot him", one user wrote. "This looks far too real".
A third added: 'Prince George has a toy gun ....really!'.
What do you think about the toy gun?
Sad to see George playing with a gun when the whole country has a gun/knife crime situation.
Princess Charlotte in particular, already known for her impeccable and charming foreign diplomacy skills despite her young age, proved to be the star of the show with some playful antics.