Daughter of dance teacher/choreographer Ernest Belcher.
Mother of film and television director Gregg Champion.
She was filmed for the reference of Disney animators (her then-husband Art Babbitt was an animator, and supervised much of the reference filming) as a model for the heroine in Snow White and the Seven Dwarfs (1937), the Blue Fairy in Pinocchio (1940), and Hyacinth Hippo in the "Dance of the Hours" segment of Fantasia (1940) (along with Ruby Dandridge), which she also helped choreograph, in an elaborate parody of a Balanchine ballet danced by Vera Zorina in The Goldwyn Follies (1938). Marge even recalls doing some modeling for Mr. Stork in Dumbo (1941) .
Younger step-sister of late silent screen actress, Lina Basquette.