Cerball mac Faelain

✓ per the DICTIONARY OF IRISH BIOGRAPHY (Aynsley's check, 23 Jul 2026): CERBALL MAC FAELAIN, KING OF THE UI FAELAIN - father of Sadb (I99662), the 1st wife of Diarmait MacMurchada. The UI FAELAIN were one of the THREE ruling septs of the UI DUNLAINGE, the dynasty that held the over-kingship of LEINSTER in rotation c.750-1050, based on the northern Liffey plain (Airthir Liphi); their royal seat was Naas (Nas na Riogh), co. Kildare, and their late-medieval descendants took the surname O'BYRNE (O Broin). *** THE CLIMB ABOVE HIM = NOTE-ONLY, documented in the medieval Leinster genealogies (Book of Leinster; Rawlinson B502) but NOT wired from memory (fabrication risk): the Ui Faelain descend from FAELAN MAC MURCHADA (d.738), eponym of the sept, son of MURCHAD MAC BRAIN, of the Ui Dunlainge, whose eponym DUNLAING (5th c.) descended from the legendary CATHAIR MOR, King of Leinster, and the Laigin. The ~13 generations between Cerball (fl. c.1130) and Faelan (d.738) are named in the tracts but need the actual Leinster genealogy (or O'Hart's 'O'Byrne of Leinster' pedigree) to wire; above Cathair Mor it is legend, kept note-only (as Milesius/Noah above Brian Boru, Cerdic/Woden above Alfred). Direct ancestor - the one sourced rung of the Leinster royal climb. Added 23 Jul 2026.