The patronym borne by Suibne is the same as that of the reigning Máel Coluim mac Cináeda, King of Alba. This patronym could be evidence that he and Máel Coluim were related. One possibility is that Suibne's patronym shows that he and Máel Coluim were brothers, and that Suibne had been placed upon the throne in a region occupied by the "Gall Gaidheil". In support of such an act is the fact that the twelfth-century "Prophecy of Berchán" associates Máel Coluim with Islay and Arran, and the claim by Ailred, Abbot of Rievaulx that Gallovidians were vassals of Máel Coluim's eventual successor Máel Coluim mac Donnchada, King of Alba. Máel Coluim certainly extended Scottish royal authority southwards into Lothian, and Strathclyde. If he had indeed managed to insert a brother into Galloway it could suggest that he possessed overlordship there as well, perhaps after his annexation of the former kingdom of Strathclyde. The notices of Suibne's demise, therefore, could be the first record of Scottish control of regions south-west of the River Clyde. If Suibne and Máel Coluim were not brothers, Suibne's patronym could instead be evidence that he was a son of Cináed mac Duib, King of Alba. This could mean that Máel Coluim allowed Suibne to reign over the "Gall Gaidheil" as a way of restraining him from claiming the kingship of Alba.