You can confirm this if there are records to support it.www.emeraldancestors.com
an Irish History Foundation has birth and marriage records
for most Irish counties including Fermanagh. There is only 1 parish in Fermanagh that goes back far enough.
Donated records to www.familysearch.org
the LDS, can be correct but there maybe difficulty verifiying.
My husband's family is an example there are birth years and a marriage year of 1811 in the IGI but the actual parish registers had been destroyed by fire, the only information I was able to find was the son's born to the couple, 1813 and 1816.