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As you know from the civil marriage record, Loughlan was a coachman, his father was Stephen and Loughlan's residence at marriage was Killeagh Co. Cork.
I searched on the subscription site Roots Ireland and there was no Loughlan Lawless baptismal records anywhere in Ireland and no Stephen Lawless marriage record anywhere in Ireland in the first halft of the 19th century. I also checked on the free site www.irishgenealogy.ie but found no records.
There were only three Stephen Lawless Griffiths Valuation records in Ireland: Whistlemount townland Liscartan civil parish Co. Meath Menlough in Oranmore parish in Co. Galway Largan townland Donagh Patrick civil parish Co. Galway
There are three Stephen Lawless death index records on the free site www.irishgenealogy.ie 1866 1868 1876 all in Co. Galway and I assume two of the three records relate to the two Stephen Lawless Griffiths records above.
You may want to add Loughlan to our XO Chronicles site https://irelandxo.com/ireland-xo/history-and-genealogy/ancestor-database