I have found more information regarding this couple. They appear to have been married in Gosfield, Essex County, Ontario:
http://www.rootsweb.ancestry.com/~onessex/western.htmThere is also an interesting history of the Stewart family in:
Commemorative biographical record of the county of Essex, Ontario : containing biographical sketches of prominent and representative citizens and many of the early settled families
http://www.ourroots.ca/e/toc.aspx?id=3107Also, today I was reading that Stuart is used mainly by Catholics and Stewart by Protestants.