Events
Date of Birth: unknown.
Place of Birth: unknown.
Date of Death: after 1218. Probably after September 1228.
Place of Death: unknown.
The dates are given by the Complete Peerage (11:321).
Relationships
Father: William de Briouze, lord of Briouze in Normandy and of Bramber, Sussex.
This relationship is given by the Complete Peerage (4:193; 11:321) and by Keats-Rohan (p. 346, p. 460).
Mother: Bertha of Hereford.
This relationship is given by the Complete Peerage (4:193; 11:321) and by Keats-Rohan (p. 460).
Spouse: William de Ferrers, third earl of Derby.
This relationship is given by the Complete Peerage (4:193; 11:321) and by Keats-Rohan (p. 460). Phillips (DERBY) notes that despite a charter referred to by the CP 14 being spurious, the identification of Sibyl as the wife of William is sound.
Spouse: Adam de Port.
This relationship is given by the Complete Peerage (11:320-321).
Children (by William):
(Complete source citations for facts about the children on this page are currently outside of the scope of this project. Most information below comes from Keats-Rohan.)
William de Ferrers (died 22 September 1247), fourth earl of Derby, married Agnes, daughter of Hugh, earl of Chester.
Hugh de Ferrers.
Thomas de Ferrers.
Pernel de Ferrers married Hervey Bagod of Stafford.
References
Cokayne, George Edward, and Vicary Gibbs; et al. The complete peerage of England, Scotland, Ireland, Great Britain and the United Kingdom, extant, extinct, or dormant [2nd ed.]. (London: St. Catherine Press, 1910-59).
Keats-Rohan, Katharine S. B. Domesday Descendants: A Prosopography of Persons Occurring in English Documents 1106 - 1166. (Woodbridge: 2002).
Phillips, Chris. “Some corrections and additions to the Complete Peerage.”