Livingstone's brother, Hilliard Marks, was a radio and television producer who worked primarily for his future brother-in-law, Jack Benny.

Marks's youngest daughter, Sadie (her name was anglicized), was very impressed by this comedian who played a violin as part of his act.

They met again a year later, while she was said to be working as a lingerie salesgirl at a May Company department store in downtown Los Angeles[9] – and the couple finally began dating.

He visited her at the May Company almost daily and was reputed to buy so much ladies' hosiery from her that he helped her set a sales record; he also called her several times a day when on the road.

[10] Jack Benny married Mary Livingstone January 14, 1927, at the Clayton Hotel in Waukegan, Illinois, one week after proposing.

[11][12][2] Livingstone's brother, Hilliard Marks, was a radio and television producer who worked primarily for his brother-in-law, Jack Benny.

In Sunday Nights at Seven (1990), her father's unfinished memoir that she completed with her own recollections, Joan Benny revealed she rarely felt close to her mother, and the two often argued:She had so many good qualities – her sense of humor, her generosity, her loyalty to her friends.

But NBC received so much fan mail that the character was revived into a regular feature on the Benny show, and the reluctant Sadie Marks became a radio star in her own right.

Livingstone's "chiss sweeze sandwich" order in a lunch counter sketch was referred to for several years afterwards (episode 333; October 27, 1946).

The following week, Benny devoted much of the show to poking fun at the tongue twister, chastising her for using the made-up phrase "grass reek".

Mary then took great satisfaction out of making Jack admit to the millions of listeners that "grass reek" did exist ("Boy did that grease rack!"

The letters often included comical stories about Mary's (fictional) sister Babe – similar to Sadie's real sister Babe in name only – who was so masculine she played as a linebacker for the Green Bay Packers and worked in steel mills and coal mines, or their ne'er-do-well father, who always seemed to be a half-step ahead of the law.

Livingstone made few appearances on the television version – mostly in filmed episodes – and finally retired from show business after her close friend Gracie Allen did so in 1958.

Her Washington Post obituary quoted Livingstone about her stage fright: "It ended up with every Sunday night being the most torturous day of the week," she once said.

[22][23] After writing a biography of her husband, Livingstone – whose surname is often misspelled without the 'e', as with her star on the Hollywood Walk of Fame for her contribution to radio[24] – died from heart disease at her home in Holmby Hills on June 30, 1983, five days after her 78th birthday, though several outlets reported her age as 77.