As royal followers well know, Prince William and the rest of the fam are huge sports fans. Kate Middleton made not one, but two surprise appearances at Wimbledon this year. Prince Harry produced an entire Netflix series about polo. And just yesterday, Princess Charlotte showed up with her dad to watch the Lionesses battle it out against Spain.

But let's not forget one of the biggest sports fans: King Charles himself. Yesterday, the monarch posted a rare personal letter on Instagram in response to the English women's soccer team winning the EUROS 2025.