In 1958, Coates played the mother, Clarissa Holliday, in all thirty-nine episodes of the 1958-1959 situation comedy, "This Is Alice". She made guest appearances in three episodes of "Perry Mason": "The Case of the Black-Eyed Blonde" in 1958, "The Case of the Cowardly Lion" in 1961, and in "The Case of the Ice-Cold Hands" in 1964. In 1961, she was cast as Elizabeth Gwynn in the episode "The Little Fishes" on CBS's "Rawhide". Coates guest-starred as well on three episodes of "Gunsmoke" between 1958 and 1964.