Estelle Getty wasn't meant to be a regular cast member
Estelle Getty will always be remembered as Sophia Petrillo, the mother of Dorothy (Bea Arthur). But she was only ever meant to be a recurring character. After impressing test audiences, she was promoted to a regular, whilst houseboy Coco (Charles Levin) was removed from the series entirely.
Next, Bea Arthur took offence to jokes about her appearance ...