His wife was Catherine Krai, and they had four children named Frederic, Hendrik, Susanna and Levina. Hendrik, their second child, went on to attend the University of Leiden and, becoming a famous scientist in his own right, was the editor of his father's collected works.
Ang kanyang asawa ay Catherine Krai, at sila ay may apat na mga bata na pinangalanang Frederic, Hendrik, Susanna at Levina. Hendrik, ang kanilang pangalawang anak, pumunta sa na dumalo sa Unibersidad ng Leiden at, nagiging isang bantog na siyentipiko sa kanyang sariling karapatan, ay ang editor ng kanyang ama nakolekta gumagana.