Petronille de Grandmesnil was born circa 1134 in Leicestershire, England, United Kingdom to Guillaume de Grandmesnil (c1100-c1147) and Beatrix de Rye and died 1 April 1212 of unspecified causes. She married Robert de Beaumont, 3rd Earl of Leicester (1130-1190) . Charlemagne (747-814)/s.
|Offspring of Robert de Beaumont and Pernelle de Grandmesnil (1135-1212)|
|Robert de Beaumont, 4th Earl of Leicester (c1156-1204)|
|Roger de Beaumont (c1158-1202)|
|Amicia Beaumont (c1155-1215)||1155||September 1215||Simon IV de Montfort (c1156-1187) Simon IV de Montfort (c1156-1187) Guillaume II des Barres|
|Margaret Beaumont (1180-1236)||1180 Hampshire, England||12 January 1236 Northamptonshire, England||Saer de Quincy, 1st Earl of Winchester (c1170-1219)|