Dubhaltach MacFhirbhisigh states that: "Tomás Bobhdacing, who was reared in Áth na Ríogh {Athenry} by Bobhdacing; from his rearing by him they are called 'Boidicín', and are of the lineage of Muiris mac Gearalt mac Muiris Mór." .
MacFhirbhisigh goes on to relate that they were kindred of the Mac Morris family of Brize, County Mayo, who derived their surname from another Maurice fitz Gerald, also descended from the first Maurice fitz Gerald.