'An Heir and a Spare': Prince William's Spanish relatives honour eldest daughter

The Future Queen of Spain, Princess Leonor, who is now enrolled in the military as a Dame cadet, joined her father, King Felipe for the first time to take the military salute during this year Spain's national day celebration.

It was the first time Princess Leonor took part in the salute. The heir to the throne was in in her full military uniform and arrived with her mother Queen Letizia.

The king's younger daughter Infanta Sofía was not present as she was in Wales for education.

Infanta Sofía is second in line to the Spanish throne just like UK's Prince Harry was before his elder brother Prince William and Kate Middleton had their own children.

Harry famously wrote a book titled "Spare" which contained a series of allegations against senior members of the British royal family.

His relations with the royals deteriorated after the publication of the book just months before the coronation of King Charles.

Harry moved to the US along with his wife Meghan Markle after stepping down as a working member of the royal family.

The saying "an heir and a spare" refers to aristocratic families needing an heir to inherit a title or an estate, and the "spare" is the younger sibling who could be the replacement if anything happened to the heir before he or she had their own children.

Prince William and King Felipe are great-great-grandchildren of King George of the Hellenes.