She was the sister of Jaime de Mora y Aragón, a Spanish actor and playboy.
She married King Baudouin in Laeken, Belgium, on December 15, 1960; at the ceremony she wore a 1926 Art Deco tiara that had been a gift of the Belgian Empire to her husband's mother, Princess Astrid of Sweden, upon her marriage to King Leopold III of the Belgians. Fabiola and Baudouin had no children.
The queen is a former nurse, a writer of children's stories, and a prominent supporter of social causes around the world. Guido Derom, an explorer, named a newly discovered range of Antarctic mountains in her honor in 1961.