that there's a fragmentary Egyptian version of the story, in which the heroine is a slave girl, and half-foreign to boot, and she manages to save up for a pair of sandals - but when she's bathing in the river, a falcon steals one of them and drops it in the garden of the pharoah, who takes it for an omen that the sun-god wants him to marry the woman whose sandal it was, and so it goes, the trying-on, she's the only one it fits (I guess that sandals were custom-woven then) and she has the other one, too...no wicked stepsisters or rivals iirc in the original version, but it seems to have been an explanatory legend of how a blonde Greek commoner ended up in one Dynastic family tree!