 According to Historia <unk> <unk> <unk> , the mother of Cynan 's son was <unk> <unk> Amlaíb , a paternal granddaughter of Sitriuc . Further revealed by this source is the fact that this woman 's father , Amlaíb mac Sitriuc , built and commanded a Welsh fortress called Castell Avloed . Although it is unknown how long the Dubliners possessed the fortress , in 1036 another son of Sitriuc was slain in Wales by an apparent kinsman , an event which could be evidence of a struggle for control of the site . Echmarcach 's aforesaid expulsion of Sitriuc from Dublin in the same year could in turn indicate that this exiled monarch sought refuge in Wales . 
