Chiara became pregnant but, before she was due to give birth, the plague hit Milan and she was persuaded to leave the city for the relative safety of nearby Pavia to stay with wealthy friends of Fazio. Thus Cardan was born in Pavia but his mother's joy was short lived when she received news that her first three children had died of the plague in Milan. Chiara lived apart from Fazio for many years but, later in life, they did marry.
Chiara naging buntis ngunit, bago siya ay dahil sa bigyan kapanganakan, ang mga salot hit Milan at siya ay hikayat na mag-iwan ng lungsod para sa kaligtasan ng mga malapit na kamag-anak Pavia upang manatili sa yumaman ng mga kaibigan Fazio.