The extra part lasted several days and, before she left the studio, Shannon was offered a role in a Bert Lytell comedy, Easy to Make Money (1919), which sparked her career.

Shannon was chosen as one of the WAMPAS Baby Stars of 1923, along with Eleanor Boardman, Evelyn Brent, Dorothy Devore, Virginia Browne Faire, Betty Francisco, Pauline Garon, Kathleen Key, Laura La Plante, Margaret Leahy, Helen Lynch, Derelys Perdue, and Jobyna Ralston.

"[4] Despite good reviews and a promising future, Shannon's last movie role was as Ruth Morris in Through Thick and Thin (1927) opposite William Fairbanks.

[5] She and Joseph Jackson (June 8, 1894 – May 26, 1932), screenwriter and former press agent, were married April 10, 1927, at the Wilshire Boulevard Congregational Church, Los Angeles.

In August 1935, an article in the Los Angeles Times stated that the "piquant red-haired" actress was coming out of her retirement to resume her career as she was signed to a long-term contract by Warner Bros. and given, as her first assignment, an important part in Stars Over Broadway and was to be billed as Ethel Shannon Jackson.