From Carl's research notes
There were 5 brothers and sisters or half brothers and sisters (Mackay) who immigrated to Canada from Ireland about 1830. These five people had the same mother, Barbara Ovens, and the Fathers Joseph Mackay, and William Mackay were almost certainly related, and may have been brothers. However we have not as yet been able to prove the degree of their relationship.
Record book kept by Mr Wilbert Mackay, of Sawyersville, PQ
Recently a historical society has been formed for Compton County PQ, and its record will be kept at Eaton Corner PQ, a few miles from Sawyersville PQ