B Burke: Dormant and Extinct Peerages -- Burgh-Earl of Kent
"William de Moreton (Mortaigne), Earl of Cornwall, who, rebelling against King Henry II., died a
prisoner, having had his eyes put out by order of that monarch, and his earldom of
Cornwall transferred to Stephen (Etienne) of Blois. This unfortunate nobleman left two sons
viz. Adhelm and John de Bourgh, whose son Hubert - E of Kent became one of the most eminent
and conspicuous nobles of his time." Adhelm sired the house of Clanricard etc.
See also W Betham: Genealogical Tables Tab. 708