I'm a little suspicious of your data. Bridget's DOB would normally have been a decade later than the 1828 you listed. I assumed your info was correct in doing my research. You might want to try alternative ranges.
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 Bri(dget) Murphy B 1828 somewhere in Ireland with the father's forename unknown, I found 30 rcds - too many to easily summarize here.
For Thomas Breen B 1826 +/- 4 yrs ditto, I found 9 rcds: 1823 LIM, 2-1826 TIP, 1828 TIP, 1828 KIL, 1828 CRK, 1829 LIM, 1830 KIL, and 1830 WIK.
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.