He had a relationship with Petronella Blondeel.
Child(ren):
Belgique, Flandre-Occidentale, registres d'état civil, 1582-1910
https://familysearch.org/ark:/61903/1:1:27NB-SM6
FamilySearch: Family Tree
Joannes Van Acker
Death 3 December 1798 • Zedelgem, West Flanders, Belgium
Spouse Petronella Blondeel
Children Isabella Vanacker
Lead confidence: 5
https://www.familysearch.org/tree/person/GW61-5N8
FamilySearch: Belgium, West Flanders, Civil Registration, 1582-1910
Joannes Vanacker in entry for Victoria Vanacker, "Belgium, West Flanders, Civil Registration, 1582-1910"
Lead confidence: 5
https://www.familysearch.org/ark:/61903/1:1:27NB-SM6