I have found a mention of an Ann P Fitzgerald who was listed as a sponsor at a baptism in 1817:
3. Baptism - Sutton, William, 12 Nov 1817, Address: Ballywilliam, Ballyporeen Parish, Co. Waterford; ParentS: Joseph Sutton, Catherine Hamilton
Sponsors: Rev. Sexton, Ann P Fitzgerald
I don;t know if this this related to your interests.