The Chronicle of the Princes of Wales records that "from South Wales, Gruffudd and Cynan the sons of Maredudd son of Owain son of Gruffudd son of the lord Rhys, and Llywelyn son of Owain his nephew, became reconciled to the king" in 1276.
Lord of Iscoed. 1
Inquisition Post Mortem
91. Llewelyn ap Owayn
Writ to the justice of Wales, 3 May, 2 Edw. II. 
Cardigan. Inq. Thursday after Holy Trinity, 2 Edw. II.
(Unspecified.) A commote and a half, and a 'Westwa,' held of the king in chief by the Welsh tenure 'Pennaethium' (?), viz.—by fealty and by service that he and all his tenants whenever necessary are bound to come at the summons of the king's bailiffs for the expedition of the king and his bailiffs, for three days at their own charges, and he is bound to do suit at the court of Cardigan called the Welsh county (court); and after his death the king ought to have of his goods 100s. as heriot called 'Ebedin'; and according to the custom of the Welsh his lands ought to be divided proportionally between his sons, nor can the king exact of them wardship or marriage.
His sons, Owen aged 11, and Thomas aged 10, are his next heirs. 2