The monarch has ensured the family remain united, proving so in a recent trip to Ibiza. On Monday, Letizia and Felipe stepped out on the Spanish island to visit the Monographic Museum and Necropolis of Puig des Molins.
The royal couple travelled to Ibiza from the nearby island of Mallorca, were they were believed to be enjoying their annual holiday with their daughters, Crown Princess Leonor and Infanta Sofia.
Historian Charles Powell of Real Instituto Elcano told the Reuters news agency that due to her non-royal background she “grounds” the king.
He said: “I think (their marriage) was a very positive thing.
“What she brings to the marriage is basically that she grounds him.
“She makes him aware of everyday issues, everyday problems.”
The trip comes after Spain’s monarchy saw itself at the centre of a scandal that forced former king Juan Carlos to self-exile.
Spanish authorities have launched an investigation on whether Juan Carlos received a secret commission for helping secure a £5.5 billion Saudi rail deal.
Felipe VI became king of Spain in 2014 following the abdication of his father Juan Carlos.
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She has been placed under investigation regarding some audio tapes of a meeting between herself and retired Spanish police commissioner José Manuel Villarejo at her home in 2015.
In the tapes, she allegedly said Juan Carlos cashed in on a secret commission for his role in securing a £5.5billion Saudi rail deal.
Mr Villarejo requested her for a meeting under the excuse that Spain’s intelligence services were trying to implicate her in criminal activity.
The police commissioner later leaked the recordings to media outlets.
Juan Carlos, in his letter to Felipe regarding his decision to move abroad, wrote: “Guided by my conviction I can offer the best service to Spaniards, its institutions and to you as King, I am communicating my decision to move away from Spain.
“It’s a decision I am taking with deep feeling but with great serenity.
“I have been King of Spain for almost 40 years and during that whole time, I’ve always wanted the best for Spain and for the Crown.”
He signed off the letter: “With affection as always, your father.”
Felipe has not addressed his father’s decision to leave Spain.