Petronille d'Oisy, Abbess of Cysoing, was born circa 1137 to Gautier d'Oisy (-1147) and Ide de Mortagne (c1122-c1169) and died after 1174 of unspecified causes. She married Jan I van Peteghem (c1120-1154) . She married Roger de Landas (-1171) . Alfred the Great (849-899)/s, Charlemagne (747-814)/s, Hugh Capet (c940-996)/s.
|Offspring of Petronille d'Oisy and Jan I van Peteghem (c1120-1154)|
|Jean II de Cysoing|
|Johanna van Peteghem|
|Elisabeth van Peteghem (c1154-c1201)||1154||1201||Jean I de Nesle (1153-1214)|