I have John Campbell married to Mary Mc Conville and I have a copy of one of the children's birth cert, which is how I found Mary's maiden name, there 1st child was born around 1858. Strokestown. I think they could have been married in Strokstown also

?? but not 100% sure, This is where they were living but a family member seems to think they may have come from Northern Ireland...How would I go about trying to find any more on John & Mary.
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