Isabel de Clare was born 2 November 1226 to Gilbert de Clare, 5th Earl of Hertford (1180-1230) and Isabel Marshal (1200-1240) and died 10 July 1264 of unspecified causes. She married Robert de Brus (c1210-1295) 12 May 1240 JL . Charlemagne (747-814)/s, Hugh Capet (c940-996)/s, William I of England (1027-1087)/s.
|Offspring of Robert V de Brus, Lord of Annandale, Lord of Ireby, Constable of Carlisle Castle, Sheriff of Cumberland and Isabel de Clare (1226-1264)|
|Isabel de Brus (1249– c1284)|
|Robert de Brus (1243-bef1304)||July 1243 Writtle, Essex, England, United Kingdom||April 1304 Holm Cultram Abbey, Cumberland, England, United Kingdom||Marjorie, Countess of Carrick (1256-1292) Marjorie, Countess of Carrick (1256-1292) Eleanor N (?-1331)|
|William de Brus|
|Bernard de Bruce|
|Richard de Brus (?-c1287)|
|Constance de Brus (1251-?)|