Maria Cristina, Infanta of Portugal and Spain was a daughter of Infante Francisco de Paula of Spain and his wife Princess Luisa Carlotta of BourbonTwo Sicilies. She became an Infanta of Portugal by her marriage to Infante Sebastian of Portugal and Spain.
Maria Cristina was one of eleven children born to Infante Francisco de Paula of Spain and Princess Luisa Carlotta of BourbonTwo Sicilies in Madrid. Her father was in turn a younger son of Charles IV of Spain. Her mother was a daughter of Francis I of the Two Sicilies.
Source: Wikipedia