Carlos Javier, Head of the Carlist dynasty, as he is described in the article, and Duke of Madrid, had a political meeting with members of the Carlist party in the Netherlands last April 8.
They discussed about the Spanish political situation, including Catalonia, as well as about European topics.
His brother, "Infante" Jaime de Borbón-Parma, Duke of San Jaime (Prince Jaime de Bourbon de Parma, Dutch Ambassador) was also present.
https://www.monarquiaconfidencial.com/espana/Carlos-Javier-Borbon-Parma-representantes-Carlistas_0_3127487233.html
A picture of the meeting.
Some more information, with more pictures.
https://espaciocarlista.wordpress.com/2018/04/08/encuentro-en-la-haya/#more-4214
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