The crossword solutions for the term 'Daughter of Juan Carlos I' are Elena (5 letters), SPAIN (5 letters), Rey (3 letters), Reyes (5 letters), SAN (3 letters), and ALFONSO (7 letters). Elena is the daughter of Juan Carlos I, who was the King of SPAIN from 1975 to 2014. Her full name is Elena María de las Mercedes de Borbón y de Grecia. She is also known as Princess of Asturias, a title given to the heir apparent of the Spanish throne. SPAIN is the country where Juan Carlos I reigned as King. Rey is the Spanish word for King, while Reyes is the plural form of the same word. SAN is the Spanish word for Saint, and ALFONSO is the name of Juan Carlos I's father, who was the King of SPAIN from 1941 to 1975.