Complex sentence: Fernández Cavada was one of three sons born in Cienfuegos, Cuba, to Isidoro Fernández Cavada and Emily Howard Gatier; his mother was an American citizen and a native of Philadelphia.
Split into simpler sentences: Fernández Cavada was one of three sons born in Cienfuegos, Cuba, to Emily Howard Gatier and Isidoro Fernández Cavada. Their mother was an American citizen and a native of Philadelphia.