|Marlene A. Eilers Koenig collection|
On May 13, 1868, Isabel married Prince Gaetano of Bourbon-Two-Sicilies, Count of Girgenti, son of King Ferdinando II of Bourbon-Two-Sicilies. She became a widow three years later when Gaetano took his own life. He shot himself in the head in a hotel room in Lucerne, Switzerland.
Gaetano was a first cousin to Isabel's mother and father.
Isabel was Princess of Asturias from her birth until the birth of her brother, Alfonso XII, in 1857. After he succeeded to the throne, Isabel was the heiress presumptive. She was again named as Princess of Asturias, a title she held until the birth of her niece, Mercedes, in September 1880.
Isabel never remarried. She was one of the most popular members of the Royal Family. Although the new Republican government said she could remain in Spain, she chose to go into exile with the rest of the Spanish royal family. She died on April 22, 1931 in France, only five days after her nephew, King Alfonso XIII was forced into exile.