Isabel married first to Gilbert de Lacy (died in 1230) and they had the following children:
Margery de Lacy Maud de Lacy Walter de Lacy Isabel married second after 1230, Sir John Fitz Geoffrey who was a son of Geoffrey Fitz Piers, Earl of Essex. Sir John Fitz Geoffrey was Justicar of Ireland 1245 – 1256. He died on November 23, 1258. Isabel and John FitzGeoffrey had the following children: Isabel FitzJohn Sir John FitzJohn Richard 1st Lord Fitzjohn Maud FitzJohn Aveline FitzJohn Joan FitzJohn
We are descended from 6 of her children, out of 9 known ones. CoA says "sister of John Bigod" but the latest scholarship does not in any way confirm this. There were Johns in the Bigod family, one was a nephew, a cleric and another was a distant cousin but none were her brothers who were: Roger, Earl of Norfolk, Hugh, father of Roger's heir and next earl, and Ralph. The best recent scholarships is a set of three articles published by Paul Reed FASG on the internet newsgroup soc.genealogy.medieval on the 2nd August 2000, under the title "BIGOD of Settringham, co. Yorks., and Stockton, co. Norfolk".
More About Isabel Bigod: Date born 2: Abt. 1210, ? Thetford, Norfolk.564, 564, 564, 565 Date born 3: 1210, of Thetford, Norfolk, England.566, 567, 568 Died 2: 1239569, 569, 569, 570 Occupation: Probably eventual heir of her brothers..571, 572, 573 Record Change: May 28, 2002574, 575, 576
More About Isabel Bigod and Sir John FitzGeoffrey, Justiciar of Ireland: Marriage 1: 1236577, 577, 578 Marriage 2: Aft. 1230579, 579, 580
Children of Isabel Bigod and Sir John FitzGeoffrey, Justiciar of Ireland are: