By the time Minnie landed a role in Freaks in 1932, the sideshow world already had a "Koo Koo, the Bird Girl" - Betty Green - but this didn't stop Minnie's managers from dressing her in a feathery costume, too. Though she has no lines in Freaks, she made a lasting impression on moviegoers when she shimmied on the table during the wedding feast of Cleopatra the aerialist and Hans the dwarf. Thus it was Minnie who was best remembered as "Koo Koo", not Betty Green, although the two are frequently confused. Later, Minnie worked at Coney Island as "Koo Koo, the Blind Girl from Mars", where she confounded spectators by failing to respond to visual stimuli. Her blindness is just one of a host of symptoms that characterize some types of primordial dwarfism.
It's unknown exactly how long Minnie was with the circus or when she died, but some accounts claim she was still living (and was nearly run over by a car) in 1960, making her at least 80 years old.