Francine Descartes

Helena officially remained Descartes' servant, and René referred to Francine as his niece, but both were included in his life.

In 1640 Descartes wrote that he would bring his daughter to France to learn the language and be educated,[2] but before that could happen, Francine died of scarlet fever at the age of five.

Russell Shorto postulated that the experience of fatherhood and losing a child formed a turning point in Descartes' work, changing its focus from medicine to a quest for universal answers.

Helena may have moved with Descartes to his next addresses — including in 1643 to Egmond-Binnen — where in 1644 she married the local innkeeper Jan Jansz van Wel.

Notary acts discovered by Jeroen van de Ven show that Descartes provided the 1000-guilder dowry for this wedding.