MAHARs in the 1880s

Have a William Joseph Mahar born on 5 Mar 1868 in Dublin, Ontario, he later moved to North Dakota in USA. Looking for more information on his family that stayed behind in Ontario. His father was John Mahar and I believe his mother was Margaret Dyrure. They had at least 4 children: Minnie who went on to marry Patrick Dougherty. Frank who I know nothing about. William Joseph married Nellie Burton and lived in North Dakota, USA. Louis James who also moved to North Dakota, USA and married Sara Ann Burton. I believe that John came from Ireland, but no evidence. I might have located them at Saint Columban Roman Catholic Cemetery; Margaret and John. I am hoping to find some sort of record that links the family back to Ireland. Also wish to know more about Dublin and Hibbert Township. I live in USA and wondered if any of those area resources are available online?
Thanks so much.

Lori Bast