Rosemary Clooney (1928-2002) was a singer and actress whose career came to prominence in the 1950s, with a starring role in the film White Christmas (alongside Bing Crosby and Danny Kaye). Clooney's 1956 recording of "I've Grown Accustomed to Your Face" was adapted into a famous Muppet variety show sketch, performed by Kermit in drag.
In 1999, Clooney appeared in episode 3826 of Sesame Street, singing the theme song. She also appeared in the celebrity version of "Sing" with Herry Monster. Clooney also appeared on the album and special A Rosie Christmas (on which Elmo also appeared)