Luísa Fernanda was the younger sister of Quen Isabel II who was swept up in the same political intrigues that clouded the life of her older sister. According to Wikipedia's article about Luísa Fernanda: "Isabella had been engaged to their first cousin Francis, Duke of Cadiz, who was known to be homosexual and rumored impotent. Their kinsman, King Louis Phillippe of France calculated that no children will be born from Isabella's marriage, and planned the crown of Spain to eventually devolve to his own grandchildren. For this purpose, Luisa Fernanda was engaged to Antoine, Duke of Montpensier (1824-90), the youngest son of king Louis Philippe, who also was Luisa's mother's first cousin." Such family love - Louis Phillippe could have worked for Lehman Brothers or Goldman Sachs! His plan almost came to pass - Luísa's daughter Maria de las Mercedes ("la reina romantica" according to Foro Dinastias) married King Alfonso XII, but she died of tuberculosis before she could produce an heir. Alfonso XII then married Maria Christina of Austria who bore children so the Spanish royal line descends from her instead of Louis Phillippe's line. Her Wikipedia article is here.