Helen Kane was at least one of the inspirations for Betty Boop. Here is a Helen Kane comic strip, which is very similar to the Betty Boop comic strip that was being run in the papers during the same period.
Helen Kane sued over Betty Boop, but lost the suit, because it was pointed out that the act wasn't original to her. Still, her comic strip proclaims her as the "Original Boop-Oop-A-Doop Girl".
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