My Geoghegans start with a Christopher Geoghegan born
1850 in Meath, ireland married a Bridget Molly in Dublin

In our research we have found the following information
On Geoghegans, not sure if any connection to above but may
help someone.

Geoghegan Marraiges

Charles Bolton Geoghegan full age Bact Esquire from upper Rathine
married Adelaide Harris from Lorne Place 26 march 1864,
St peters.Dublin
Fathers William More Geoghegan Merchant
John Harris Commisioner?
Witness Henry Bolton and J Molloy

Honor Geoghhan 35 yrs Widow 47 New Street Dublin Charwomen
married Richard Jordan aged 34 yrs Widow 13 Fainhally Lane, Dubin Dealer
At St Nicholas Church Dublin on 8 February 1864
Fathers
John Geoghan
John Jordon
Witness as above

Bryan/Bernard Geoghan 35 yrs Bach,Labourer, Stones Town Meath married
Mary Smith 25 yrs Spin Kilbride Meath
on 14 january 1864, Kilbride Tuam Meath
Fathers
Pat Geoghan Labourer
Martin Smith
Witness James Griffen, Margaret Smith

James Geoghegan 25 yrs Bach labourer, Cousins Place, Westmeath married
Mary Coleman aged 21 yrs Spin, Servent, Ath Lane, Westmeath
Fathers
Both dead, both there occupations Farmers
Witness James Costello and Biddy Malone

Andrew Geoghegan full age Bach Blacksmith. Roachfield, Kings Co married
Ellen Waters full age Spin Rathbourne, Westmeath
6 Feb 1864 Mullingar West Meath
Fathers
Mathew Geoghegan Blacksmith
Micheal Waters Herd ( guess heardsman )
witness Richard and Eliza Hughs

John Geoghegan 32yrs bach Farmer Drumkieron Cavan
Married
Briget McKeiron 22yrs Spin Corderlay,Cavan
on 8 Feb 1864 Ballinagh Cavan
Fathers James Geoghegan Farmer (d )
Francis Mc Kerion Farmer
Witness Mathew Donnely Susan Cosgrove

Ellen Geoghegan 29 yrs Widow Boleybeg,Queens Co married
John McGrath 35 yrs Bach Farmer Graughnastymutton, Quuens Co
On Jan 27 1864 Abbeliex, Ballinakill. Queens Co
Fathers
John Lalor Farmer ( wifes father )
John Lalor Farmer
Witness Patt Baylon,Kate Lalor

Catherine Geoghan Minor ,Spin ,Philipstown, Tullamore
married
Jereniah Hyland Full age bac Serg 67 Foot????field, Queens
On 9 Jan 1864 Philipstown Quuen Co
fathers
James Geoghan Hatter (d )
Andrew Hyland Farmer ( d )
Witness Mary Colgan Eliza Geoghan

Births

6 Jan 1876 ? Fitzharris, Rotunda Hospital, Dublin, mother Rose Geoghegan, father John Frizharris dealer

Martin Peter b 3 jan 1879 Castleknock, North Dublin,
mother Elen Geoghegan, father John martin Herds

David Morriss 14 Feb 1876 Finglass, Dublin, mother
Elen Geoghegan, father John Morriss Constable Ric

James Geoghegan 1 march 1876 New road, Dublin South, father Parick Geoghegan, mother Catherine Doran

Bridget Douglas 15 march 1876 South Plunket St, Dubin South
catherine Geoghegan mother, John Douglas labourer

Nicholas kennedy 16 Jan 1876 Brassan St Dublin, mother Jane GGeoghegan and father ? Nichlas

Mary Anne McDonnell 21 Feb 1876 ,18 Thomas St Dubin, mother
Mary Geoghegan,F Patrick McDonnell

Francis John Geoghegan 12 Feb 1876 52 Upper Leeson St, Dublin
father Jacob Thomas Geoghegan Barrister in law, mother Emma
Baxter

Eliza Jane Horan 30 Dec 1876 Anne Steet, Dundalk Louth,
mothe mary Ann Geoghegan, father John Horan Constable

Margaret Kelly 13 Jan 1876 Ballylyre, Nass Kildare
mother Bridget Geoghegan, father Nicholas Kelly Tailor

James Geoghegan 7 Feb 1876 Nass Kildare
father Micheal Geoghegan carman, mother Mary Hyland

William Geoghegan 26 feb 1876 Fitspatrick St, Kingstown Rathdown
father Patrick Geoghegan Lab crop Avne, mother Eliza Masterson

Ellen Geoghegan 2 Feb 1876, Mullingar Quarry West Meath
father Edward Geoghegan Mason, mother catherine Flanagan

Jane Geoghegan 13 jan 1876 Lurgan Portadown Armagh
father James Geoghegan farmer, mother Ann Jones

Christopher Geoghegan or Gregan baptized 20 June 1858 Illegimate father Mr Christopher Gregan, mother Anne Bacon
Sponser Bridget Brien

really do hope this helps someone.

information research by my mother Mary Heffernan ( nee Nash ) who was married to Patrick Heffernan whos mother eas Mary Geoghegan