Complex sentence: The Marchioness Leonor of Távora with her husband, Francisco Assis, Count of Alvor and a former viceroy of India, headed one of the most powerful families in the kingdom, related to the houses of Aveiro, Cadaval and Alorna.
Split into simpler sentences: The Marchioness Leonor of Távora and her husband, Francisco Assis, Count of Alvor and a former viceroy of India, headed one of the most powerful families in the kingdom. They were related to the houses of Aveiro, Cadaval and Alorna.