According to the Spanish news site, El Mundo, as well as the magazine Hola!, not one member from the Spanish royal family will attend the upcoming princely wedding in Monaco on July 1 and 2:
The reason that the royal family will not attend is that the invitation was addressed to King Juan Carlos only and he cannot come because he is still recovering from his recent knee surgery.
Huh.
Interestingly, there is nothing on the official website for the royal family of Spain, Casa de Su Majestad El Rey, confirming their non-attendance to the wedding.
Hopefully, there is a misunderstanding and hopefully at least one member from the royal house of Spain will attend.
Source: El Mundo.es and Hola.com
Photo courtesy of: Wikipedia
The Royal Correspondent 
spanish royals were pissed that albert questioned Madrid’s security during their bid for the olympics, they forget that rainier basically supported queen victoria eugenia during the last years of her life, but Monaco will always stay as a princely state whereas spain will soon be a republic.
and who can take the greek royals seriously? who cares about constantine at this point>