Alison:
Welcome to Ireland Reaching Out!
I searched on the subscription site Roots Ireland and found an 1816 baptismal record in Kill for an Eliza Byrne with father Denis and mother Mary. Note one of the sponsors was a Sullivan so likely this record is for a daughter of Denis Byrne and Mary Sullivan. A baptismal record for Denis would not be available since Naas records start in 1813.
Roger McDonnell
Name:Eliza ByrneDate of Birth:
Date of Baptism:22-Sep-1816Address:KillParish/District:KILLGender:FemaleCountyCo. Kildare
Denomination:Roman Catholic
Father:Denis ByrneMother:Mary UnknownOccupation:
Sponsor 1 /
Informant 1:Mr. IverySponsor 2 /
Informant 2:Jane Sullivan