Her maternal grandparents were Sicilian-born Michele De Carlo and Scotland-born Marie Purvis. She drew her stage name from her grandfather.
Her mother was fascinated with actress Baby Peggy, and wanted to have a baby of her own, of the same name.
Her mother, Marie De Carlo, died in 1993, from a fall.
Her parents were Marie De Carlo, an actress, and William Middleton, a salesman.
Measurements: 34C-23-35 (1940s), 36C-24-36 (measured in 1951) (Source: Celebrity Sleuth magazine)
Miss Venice Beach 1938.
Of Sicilian and Scottish descent.
Remained good friends with Butch Patrick, during and after "The Munsters" (1964).
Resided at the Motion Picture and Television Hospital from 1998 to 2007, where she died.
She chose her own stage name by using her middle name and her mother's maiden name of De Carlo.
She had 6 hobbies: spending time with her family, golfing, dancing, drinking wine, listening to music, singing.
She was the producers' second choice to play Lily Munster, after Joan Marshall was dropped from consideration for the role of Phoebe Marshall.
Suffered a stroke in 1998.
Throughout 1937, Yvonne's mother took her to Hollywood to try to be a star, but didn't succeed and returned to Canada.
Took the part of Lily on "The Munsters" (1964) to help pay husband Bob Morgan's medical bills. Morgan, an actor/stuntman, had suffered near-fatal injuries while filming How the West Was Won (1962). By her own admission, Ms. De Carlo never imagined, at the time, that Lily Munster would become her most famous role.
Two sons - Bruce Morgan and Michael Morgan. Step-daughter Bari Morgan. Son, Michael, died in 1997.
Was a heavy smoker for many years.
Was involved in relationships with: Billy Wilder, Robert Stack, Clark Gable, Burt Lancaster and Howard Hughes.
Was only three when her father and mother split up.