- Marriage: Hugh II DE BOLBEC, Lord Of Whitchurch 
Another name for Margaret was Margery.
["Margaret" ?, "De Montfichet" ? There are many errors in the several accounts of this family. some say that Isabel was a Walter's daughter ...]
"Isabel de Bolebec, Countess of Oxford (c. 1164 - died 2 or 3 February 1245), was the eldest daughter and co-heiress of Hugh de Bolebec II, Lord of Whitchurch, Buckinghamshire, and his wife, Margaret de Montfichet. She married Robert de Vere, 3rd Earl of Oxford, and was a benefactress of the Order of Friars Preacher (Dominicans) in England.
Isabel de Bolebec was the daughter and co-heiress of Hugh de Bolebec II (died c. 1165), Lord of Whitchurch, Buckinghamshire, and his wife, Margaret de Montfichet. She had a brother, Walter, and a sister, Constance, the wife of Ellis de Beauchamp. In 1206-7 she and Constance were co-heirs to their niece, Isabel de Bolebec, daughter of their brother, Walter, and wife of Aubrey de Vere, 2nd Earl of Oxford. ..."
Source <The History and Antiquities of the County of Buckingham, Volume 3> Par George Lipscomb:
"Pedigree of BOLEBEC
Richard Lord Mont Fichet = _
- Avelina ...
- Philippa ...
- Margaret = Sire Hugh de Bolebec, Lord of Missenden, & ...
- Hugh de Bolebec ...
- Walter de Bolebec, of Bolebec Castle, heir of his brother and nephew w. Ob. 32 Hen. II = _
- Isabel, dau. and Heir, nine years old at her father's death; ... = Robert de Vere, son of Alberic, Earl of Oxford, ..."
Margaret married Hugh II DE BOLBEC, Lord Of Whitchurch  [MRIN: 2140], son of Walter DE BOLBEC  and Eleanor . (Hugh II DE BOLBEC, Lord Of Whitchurch  was born in , Buckinghamshire, England and died in 1165-1166 in , , England.)