My 2nd Great Grandparents John and Roseanna Paton came from Donegal. I have no marriage records but they had eight children, the first Michael in 1834 and the last Maria in 1851. Their last three children, Patrick, William and Maria were baptised in Killygordon. Roseanna's father was Thomas McBrearty. I have not been able to trace any details of John or Roseanna in Donegal part from the birth of their children?
The marriage records for the RC parish of Donaghmore began in 1846, so there will not be a marriage record. Attached is a petty sessions record for John Patton of Killygordon who let his horse graze on the public land, and was fined two shillings. This record is from 25 May 1859. Additionally, there is a Griffith's Valuation record for William Patton as a tenant in Killygordon from 1857 that you can find on askaboutireland.ie.
Regards,
In 1826, the following heads of household named Patten were listed in the Tithe Applotment Books for Donaghmore parish, Donegal:
There was one McBrearty:
I hope this is helpful.
Have you looked for deaths of John and Roseanna at irishgenealogy.ie civil records? And have you looked for them in the 1901 Irish census? Just a couple of ideas.