A possible?
Marriage: Ancestry.ca
Isaac Hopkins, 28, b Hanover, lumberman, living Tobermoray, s/o John Hopkins & Mary Ann Hopkins, married Hazel Olive Young, 19, b South Hampton, living Tobermoray, d/o Alexander Young & Hattie Bordon?,witn: Donald Gillies, & W W Ramsbury, 11 Sept 1907, St Edmunds, Bruce County, Registration# 005351.
Hanover is near Ottawa so this likely isn't your Isaac.
1901 census an Isaac Hopkins,labourer, boarder, b Jan 1877, is with Edward & Harriet Hopkins in St Edmunds, Bruce County.
1901 and 1911 census on
www.automatedgenealogy.com1881 census on
www.familysearch.orgNormanby, Grey South
Mary Ann Hopkins, 26, b Ont, farm servant, Church of Englnd
Isiac Hopkins, 4, b Ont
Working for Henry & Mary A McMahon.
Did not find him on 1891 census. With grandparents? Relatives? He would be 14-16. Maybe working. Dead? No death or marriage found for him on Ancestry.ca
Mary Ann is on 1891 census with husband Henry Davis and two chidren, Margaret Ann 1 and Harriet Elenea? 5/12. No sign of Isaac Hopkins.