I do find it odd however that his sons opted for the Escorial and not for a French burial of a man they considered to be the King of France.
Infante don Jaime’s remains have been at El Escorial since 1985, when his remains were brought to Spain from abroad, with his mother and brothers. His sons were present at the ceremony and showed no objections. So, I do not understand your question. Surely, LA has been informed, but he is simply transferred to the Patheon from the Rotten Chamber. It was simply a matter of time that this moment would arrive.
By moving don Jaime to the Pantheon king Felipe VI claims his great uncle as Infante of Spain how do Luis Alfonso and his Legitimist supporters feel about this?
Was LA consulted about the move? Did he agree?
According to this article, the remains of Infante don Jaime will be soon transferred to his final resting place at the Pantheon of Infantes of El Escorial.
https://monarquia.elconfidencialdigital.com/articulo/la_nobleza/patrimonio-nacional-prepara-traslado-infante-don-jaime-panteon-infantes/20190301110559023645.html
A picture of his tomb, between his brothers Alfonso and Gonzalo.
The inscription will say: "Jaime. Alfonso XIII's son", in latin.
Of course no mention to this "foreign pretension" titles.
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