Isabel de Avenell

  General Notes:

Isabella, the natural daughter of William the Lion by a daughter of Richard de Avenal, married Robert de Ros, son of Everard de Ros and Rose Trussbut They were the parents of Sir William Ros

~Richardson's Magna Carta Ancestry: A Study in Colonial and Medieval Families, p. 826 ⁸²¹

Isabel married William I "The Lion" King of Scotland, son of Henry mac Crínán Earl of Huntington and Ada de Warenne. (William I "The Lion" King of Scotland was born in 1142-1143 in Scotland, died on 4 Dec 1214 in Stirling, Stirlingshire, Scotland ⁸⁷¹ and was buried in 1214 in Arbroath Abbey, Aberbrothock, Scotland ⁸⁷¹.)