Hi Linda,

Is this Eliza in the 1881 census (from Familysearch.org)? If so, she was a widow at that date:
Household:
Name Marital Status Gender Ethnic Origin Age Birthplace Occupation Religion
James MCGLENNON M Male Irish 39 O Presbyterian
Anne MCGLENNON M Female Scottish 36 O Presbyterian
Fredie MCGLENNON Male Irish 12 O Presbyterian
Thomas MCGLENNON Male Irish 11 O Presbyterian
James MCGLENNON Male Irish 9 O Presbyterian
Abigail MCGLENNON Female Irish 7 O Presbyterian
Mary MCGLENNON Female Irish 4 O Presbyterian
Annie MCGLENNON Female Irish 2 O Presbyterian
Eliza MCGLENNON W Female Irish 73 Ireland Presbyterian
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Source Information:
Census Place Haldimand, Northumberland West, Ontario
Family History Library Film 1375876
NA Film Number C-13240
District 124
Sub-district B
Division 1
Page Number 67
Household Number 337

I believe the Canadian censuses are easily available - could you check earlier ones to see what birthplace was given for John?

Sue