I research the Irish Family History Foundation's database. It contains 12,800,000 surviving rcds for abt 70% of Irish counties. Rcds are increasingly sparse B4 1840, rare B4 1800. Cos. Donegal and Derry were recently added to the database.
Note 1 - Without a KNOWN county, the chance of an ancestor's rcds NOT being in this database is AT LEAST 30%.
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 Ann(a)(e) Kinsella B 1840 +/- 4 yrs somewhere in Ireland with a father forenamed Pat(rick), I found 2 rcds: 1836 Wicklow, and 1843 Dublin.
For Pat(rick) Kinsella M 1838 +/- 4 yrs somewhere in Ireland, I found 11 rcds: 1834 KID, 1839 KIL, 1839 TIP, 1840 TIP, 1840 CAV, 1840 KIL, 2-1841 KIL, 1841 TIP, 1842 KID, and 1842 MEA.
For Pat(rick) Kinsella B 1820 +/- 4 yrs somewhere in Ireland with the father's forename unknown, I found 14 rcds: 1817 KIL, 1818 KIL, 2-1818 KID, 2-1818 WIK, 1820 WIK, 1820 KIL, 1821 KID, 2-1822 KIL, 1823 WIK, and 1823 KIL.
One or more of the above MAY be for your ancestors. You will need an exact DOB, parent(s) name(s), and/or placename(s) to pick which, if any, is(are) correct. Your knowledge of the mother's forename will help.
Note - I have looked at several Kinsella posts. I haven't had much luck in answering any of them satisfactorily. It may be that the Kinsella surname is prominent in areas of Ireland for which rcds haven't been transcribed. Suggest you wait until the database is more complete.
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.