When Clayton Henry Siccardi was born on 30 May 1918, in Brooklyn, Kings, New York, United States, his father, Henry Louis Victor Siccardi, was 22 and his mother, Geraldine Rambo, was 16. He married Jeanne Joy Klopfer Keiter on 18 May 1939, in Orange, California, United States. He lived in United States in 1949 and Los Angeles, Los Angeles, California, United States in 1950. He died on 21 February 2002, in Newport Beach, Orange, California, United States, at the age of 83.
Italian (northwestern): patronymic from the personal name Siccardo, from an ancient Germanic name composed of the elements sigi ‘victory’ + hard ‘hardy, brave’.