4If born after 1863, then the civil Birth entry, with the parents names, and address should be available here:IrishGenealogy.ie, for Free.
Similarly, if Protestant, or Jewish, their parents civil marriage will likely be on the site, and a sub-set of any Catholic Church marriages / baptisms, if periodically wanting a few graven images and a bit of coveting, though often at a diocese level, e.g. Pay and Mary of Cork were married Dec 1851, which ain’t that helpful.
Death entries, with cause, and often the names of a family member present at death, are similarly available on the site, for dates after 1863.
Though not all surviving registry images have been uploaded, as of Nov 2020, the record sets are grouped by Superintendent District, not Registration District (town), County, or Province. Add the mix of the 3 main Irish dialects, and English, on the registers, after 1922, poor cursive handwriting, a dozen spellings of almost ever Irish surname, and minimal indexing, you may end up spending many an hour trying to find a few bodies.
Add everyone loved a Mary, with many a family having a couple, after they’d run through the 5 standard girls names, so a village / parish may churn out a dozen Mary McCathys’ a year, which in combination with a half a dozen Pat and Mary McCarthys’ as parent, and you’ll need to take a note of the address, and father’s occupation, to differentiate the superficially identical sets.
The 1901 and 1911 census, are also online, and again for free, here. Though birth dates are typically to the nearest 5 years, the place of birth typically the county, and you’ll likely find many a set with a Pat and Mary as the parents, with a Pat, Mary, John, Ellen, Cornelius, Margaret, ... as kids. So you’ll again be wanting to differentiate superficially identical sets on the fathers occupation, and residence, as given names, and dates are near useless.