It was their first joint appearance abroad.
Without King Felipe and Queen Letizia, Crown Princess Leonor and her younger sister Sofía represented the Spanish crown at the European Women's Football Championship in England at the weekend.
Congratulations in the dressing room
Together with the Spanish Minister for Culture and Sport, Miquel Iceta, they attended the Spanish side's match, which defeated Denmark 1-0, at the Brentford Community Stadium, west of London, on Saturday night.
Afterwards, Leonor and Sofía congratulated the players in the dressing room on reaching the quarter-finals, according to Madrid.
Both would have been given national jerseys with the number 10 and their respective names.
A trip to the British royal family was allegedly not planned.
Most recently, the two daughters visited the Dalí Museum in Figueres alone in Catalonia.
However, the 16-year-old heir to the throne has been going her own way for a long time.
Leonor has been attending UWC Atlantic College in neighboring Wales for a year.
With her sister Sofía, who is one year younger, she traveled from Spain, where she is currently spending her summer holidays before the new school year begins.
It's not the first time Leonor and Sofía have watched a football game.
Both had already accompanied their father to Champions League games in Madrid.
Her mother is considered a supporter of women's football.
In 2019 she presented the "Queen's Cup" for the first time.