Rhett Butler is accompanied by a Scarlett body double, on the wagon during his escape from the fire. This scene was the first or one of the very first ones shot for the film, and at that stage, the role of Scarlett was not cast yet, Vivian Leigh signed on a bit later.
When Scarlett is heard gagging after hungrily eating the radish at the ruins of the Wilke's home, it is actually Olivia De Havilland who is making the sound. Vivienne Leigh thought it was unladylike to make such a grotesque sound and refused to pretend to vomit.
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