sister Margrieta Philips Leeuwenhoek married step-brother Jan Jacobs de Molijn

Date: 
May 8, 1643

Leeuwenhoek's sister Margrieta Philips Leeuwenhoek (1623-1678) married their step-brother Jan Jacobs de Molijn. At the time, she was living with her aunt in Amsterdam. Jan Jacobs was living on the Choorstraat. They were married in Amsterdam, but their betrothal was registered at Nieuwe Kerk and at Stadhuis in Delft.

From Leeuwenhoek's point of view, his step-brother and his brother-in-law were the same person.

Document: 

DTB Delft inv. 70, fol. 117v, also inv. 125, fol. 111v

Sources