He is married to Anna Maria Standaart.
Permission for the marriage has been obtained in Hontenisse on July 16, 1761.Source 1
datum: 16 jul 1761; naam bruidegom: Cornelis Claassen; naam bruid: Anna Maria Standaart; weduwe van: Jan Baart; scan: 199; link naar scan: https://www.familysearch.org/ark:/61903/3:1:3QS7-99QJ-3HXD?i=198&cc=2036997