It’s given rise to speculation that her outfit was chosen to honour King Felipe of Spain, who was at Wimbledon to cheer on Spanish player Alcaraz - who would claim victory in the match.
One Twitter user wrote that Charlotte was wearing “a [Spanish] dress from Maria to honour Felipe”, referring to the Wales children’s Spanish nanny Maria, who may have purchased the frock.
Other Wimbledon watchers noticed that Charlotte cheered on Alcaraz throughout the match and also had a sweet interaction with King Felipe.
Another commented: “Very sweet! King Felipe of Spain chats with Princess Charlotte. As her parents proudly watch. I adore how William lovingly watches his baby girl. Charlotte, like her parents & great grandma, QEII has excellent eye contact espec [sic] at such a young age.”
Others noted that Charlotte looked like “a born queen” when interacting with the king.
“Adore that look on Princess Charlotte’s face. Totally absorbed,” another gushed.
Another fan marked how “self-assured” the young royal was becoming as she gets older. “It’s lovely to see.”
Viewers also noted the close relationship between Princess Kate and her daughter on display at Wimbledon.
Kate was snapped stroking Charlotte’s face and leaning in to chat with her.
Arriving at the venue, Kate told Ella Ottaway, who runs the All England Club’s programme for children that it was “Charlotte’s first time” at the event.
“George came last year. They’ve been eagerly watching,” she revealed.
Charlotte spoke with young Mu’awwiz Anwar, whose job it was to perform the coin toss to start the match.
The 8-year-old royal presented Anwar with the coin used to decide who would serve first in the final.