He is married to Magdaleentien Huijgens.
Permission for the marriage has been obtained in Hontenisse on November 16, 1681.Source 1
datum: 16 nov 1681; naam bruidegom: Joost Geertsen; naam bruid: Magdaleentien Huijgens; weduwe van: Laureijs Piessens; scan: 11; link naar scan: https://www.familysearch.org/ark:/61903/3:1:3QS7-99QJ-34K6?i=126&cc=2036997