I research the Irish Family History Foundation's database. It contains 12,000,000 surviving rcds for abt 65% of Irish counties. Rcds are increasingly sparse B4 1840, rare B4 1800.
Note 1 - Without a KNOWN county, the chance of an ancestor's rcds NOT being in this database is AT LEAST 35%.
Note 2 - Only 1/2 of Co. Cork's rcds are in this database.
Note 3 - The RC church kept control over most parish rcds from Tipperary (north). These are ONLY available thru the Tipperary Family History Research center at a substantial fee (regardless of outcome).
For Julia Blake B 1822 +/- 4 yrs somewhere in Ireland with the father's forename unknown, I found 1 rcd in 1822, Co. Cork, Milford parish. The father's forename was Simon.
For Ellen Kirwan B 1846 (exact), Co. Tipperary, with the father's forename unknown, I found 4 rcds: 1843, 1845, 1846, and 1849. Father's forenames were Thomas, Eugene, John, and Edmund respectively. The 43, 45 and 49 rcds were in SS Peter and Paul RC parish, Clonmel. The 1846 rcd was in St. Mary's, Conmel.
For John Kirwan B 1818 +/- 4 yrs, somewhere in Ireland with the father's forename unknown, I found 20 rcds - too many to summarize here. However, 4 were in Tipperary with 1 in 1818 (exact).
For John Kirwan M 1845 +/- 1 yr in Co. Tipperary, I found 1 rcd in 1846, Dunkerrin RC parish.
For Julia Blake M ditto, I found NO matching rcds to that for John.
Google the Foundation's name to lead you to this database. Register, opt to be notified as rcds are added and browse. Pls post your search results to my genforum msg.