Born in Ferrara, during her lifetime Aguiari was often referred to as "La Bastardina" or "La Bastardella". There are several different traditions explaining the origin of this nickname, one being that she was the illegitimate child of Leopoldo Aguiari or that of his wife with the "Marchese" Bentivoglio. Another possible explanation was that she was an abandoned child raised by Aguiari. Another curiosity about the soprano was that she possessed a pronounced limp that was reportedly the result of a dog or hog eating part of her leg while she was an infant.