Eni was the brother of Raedwald, great king of the East Angles and Bretwalda.
Although of the royal house of Wuffing, Eni was never destined to be king himself but his sons Ecgric, Anna, Aethelhere and Aethelwald were all to rule East Anglia in their turn.
The Venerable Bede - Historia Ecclesiastica Gentis Anglorum
The Anglo-Saxon Chronicle