Presumably they were married in Sarah's home church at the time. It says "Holy Trinity." There is currently a Holy Trinity Catholic cathedral in Cork, but there is/was a Holy Trinity (Christ Church) Church of Ireland Church there also:
The parish records are still in existence, and available in Dublin for that parish in Cork City and for whichever parish the 3 children on the civil records were born in. They were born in Kilbrogan Townland, which is in Kilbrogan Parish, but here is the information for both possible parishes in Bandon RD, Cork
THE LIST of CHURCH OF IRELAND PARISH REGISTERS
A Colour-coded Resource Accounting For What Survives; Where It Is;
& With Additional Information of Copies, Transcripts and Online Indexes
When you find Bandon on the list, it says "see Ballymodan and Kilbrogan."
Both were in yellow, both were followed by an "M"
Kilbrogan, Diocese of Cork, baptisms 1752-1973, marriages 1753-1969, burials 1754-1992
Ballymodan, Diocese of Cork, baptisms 1695-1878, marriages 1695-1996, burials 1695-1878
yellow = RCB - Original records held by the Representative Church Body Library, Churchtown, Dublin 14
M = Microfilm copy available in the Reading Room of
the NAI only. See card index and bound diocesan
lists for further details. Note the dates of registers
covered by the films may not be those of the
originals as recorded by Miss Griffith, nor may they
be the same dates as for those registers now
deposited in the RCB Library. In most instances no
filming was undertaken of 20th-century registers
https://www.churchofireland.org/cmsfiles/pdf/AboutUs/library/registers/ParishRegisters/PARISHREGISTERS.pdf------
https://www.corkrecords.com/registers.htmThe Representative Church Body Library, Dublin, Collection of Cork Parish Registers
The original Parish Registers for most of the Church of Ireland parishes are held at The Representative Church Body Library in Dublin. These only represent those parish registers which survived the Four Courts fire in Dublin during the 1922 Civil War because they were still being held locally at the time.
City of Cork:
Holy Trinity (Christ Church): Baptisms: 1643-1976. Marriages: 1646 - 1974. Burials: 1644 - 1878.
[But I don't think the parish record will tell you any more than what is on the civil record, but I'm not positive.]
County Cork:
Ballymodan: Baptisms: 1695 - 1878. Marriages: 1695 - 1996. Burials: 1695 - 1878.
Kilbrogan: Baptisms: 1752 - 1973. Marriages: 1753 - 1969. Burials: 1754 - 1992.
They are not available online.
