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There is a record for a John and Eleanor married in the parish of Killygordan on 18-Jun-1859. Their marriage record doesn't name their parents unfortunately. Witnesses to the marriage were Patrick Andreson and Thomas Scott.
You can see the digitized original here:
I located two baptism records for children of the couple, Mary Jane baptised on 05-Feb-1860 and Robert baptised on 26-Jan-1862. If you could find an approximate birth year for John we could have a look for you.
Is there a death record or obituary your side that might shed some further light:
Scotland's People: http://www.scotlandspeople.gov.uk/welcome.aspx
As you can see the name is very common in that part of Donegal: