Her brother, Rodrigo de Castro, was governor of the Portuguese seat of Safí (Morocco).

[2] The emperor Carlos I of Spain, represented by his majordomo Pedro González de Mendoza, negotiating in the name of Leonor, urging the Duke of Gandía to accept her conditions.

After agreeing to marriage, the spouses met in Toledo in August, and the wedding with Francis Borja took place in the Royal Alcazar of Madrid in 1529.

She passed her last days in the Monastery of Sant Jeroni de Cotalba, very near to Gandia, recovering from her ailments, where she died on 27 March 1546.

At the death of Leonor de Castro, her husband, Francis Borja, saddened, resigned his goods and possessions in favor of his children, yielded the nobility titles and went to Rome, where in June, 1546, he would enter in the Society of Jesus.