King Felipe of Spain's Relative, 86, Becomes First Royal to Die from Coronavirus

The novel coronavirus has claimed its first royal, Spain’s Maria Teresa de Borbon-Parma.

The 86-year-old cousin to Spain’s King Felipe IV, who was dubbed the “Red Princess” because of her outspoken views, has died, according to her family.

The princess-activist’s passing was announced late Thursday by her brother Prince Sixto Enrique de Borbon, the Duke of Aranjuez. “On this afternoon… our sister Maria Teresa de Borbon Parma and Borbon Busset, victim of the coronavirus COVID-19, died in Paris at the age of eighty-six,” he wrote.

A mass was organized in her honor in Madrid on Friday.

Her death came as King Felipe, who tested negative for coronavirus earlier this month, made a visit to an emergency field hospital in Madrid.

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A longtime advocate of women’s rights and socialist ideas, Maria-Teresa, who never married, was born in Paris in 1933. She was the second daughter of the Carlist pretender to Spain’s throne. Following the forced exile of Spain’s King Alfonso, the Carlist movement claimed her father, Francisco Javiar de Borbon y Barganza the rightful heir to Spain’s crown, vying against the Alfonsists who eventually won favor and restoration from Franco’s regime.

Educated in France, a graduate and distinguished professor at Paris’ Sorbonne and an outspoken professor of Sociology at Madrid’s Complutense University, she held a variety of challenging ideological positions. She was also an early supporter of CIVIS (the open university system linking schools in eight European nations) and was fascinated by Islam, becoming an expert in its study, particularly as it applied to evolving women’s rights in Arab nations.

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Earlier this week, it was announced that the U.K.’s Prince Charles, 71, tested positive for coronavirus. The heir to the throne has continued working at home and his wife, Camilla, Duchess of Cornwall, does not have the virus.

Monaco’s Prince Albert, 62, has also tested positive for coronavirus, making him the first head of state to announce he had the virus.

“My symptoms are flu-like, but it feels like a pretty mild case,” he told PEOPLE. “I’ve [got] a slight fever, not really that bad. A little bit of a cough. I’d a runny nose the first few days, that was the first sign. I’ve felt a little stuffed up but that’s it.”

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