He is married to Elisabeth Glerum.
Permission for the marriage has been obtained in Kruiningen on April 5, 1798.Source 1
They got married on April 26, 1798 at Kruiningen.Source 11376. Otr. 5 april, Tr. hier 26 april, Pieter Blankenberg, jm. geboren te Nieuw Vossenaar en woond in de Reigerbergschen Polder, met Elisabeth Glerum, jd. gebooren en woonende te Kruiningen.
Kruiningen index ref. trouwen 1671-1810 https://geneaknowhow.net/script/zee/Trouwen%20Kruiningen%201671-1810.pdf