Biografía

She appeared on Broadway with Jean Stapleton in a revival of "Arsenic and Old Lace" (1987).

In 1972, Marion was hired to play Marion Cunningham in an episode of the comedy series Amor a la americana (1969) called "Love and the Happy Days". On the show, she was the mother of a teenager named Richie (played by Ron Howard) and the wife of Howard Cunningham (played by Harold Gould. Two years later, when the segment was developed into a television series called Días felices (1974), Marion was invited back to play her part and so was Howard, while Gould was replaced by Tom Bosley.

When she was starring on Días felices (1974), she and co-star Tom Bosley, who played her on-screen husband, didn't get along, at first, yet, at the series progressed, the two had bonded with each other. Bosley remained friends with Ross, until his passing on October 19, 2010.

At age 13, she changed the spelling of her name from "Marian" to "Marion" because she thought this would look better on a marquee.

She credits her late friend, character actress Sandra Gould, with helping her get the role in Días felices (1974). She was invited to a dinner hosted by Gould and a casting person from "Happy Days" also was in attendance. Not long after the dinner Marion got a call from the studio.