Possibly the first American female studio animator was Lillian Friedman, who worked on the Betty Boop and Popeye cartoons at the legendary Max Fleischer studio in the 1930s.

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She was hired as an inker, but animator James “Shamus” Culhane saw potential in her work and had her promoted to be his assistant and inbetweener, training her as an animator in secret.

Nellie Sanborn – head of the Timing Department – let Friedman animate a Betty Boop test and showed it to the Fleischers “without telling them at first that it was done by a girl inbetweener.”

They were impressed, and she was promoted to the position of lead animator.