Avelina Fitz John, d. c 20 May 1274; m. c 1257 Walter de Burgh, b. c 12 July 1271, Earl of Ulster, son of Richard de Burgh, Justice, and Egidith de Lacy. [Magna Charta Sureties]
Note: I interpret "b. c 12 July 1271" to be "d.".
---------------------
He [Walter de Burgh] married, about 1257, Aveline, sister and (in her issue) coheir of Richard FITZJOHN [LORD FITZJOHNI, 3rd daughter of John FITZGEOFFREY, Lord of Shere and Shalford, Surrey, sometime Justiciar of Ireland, by Isabel, daughter of Hugh (LE BIGOD), EARL OF NORFOLK. He died 28 July 1271 in Galway Castle, after a week's illness, and was buried in the monastery at Athassel, on the Suir, co. Tipperary. His widow died circa 20 May 1274 and was buried in Dunmow Priory. [Complete Peerage XII/2:171-3, (transcribed by Dave Utzinger)]