I checked the Roots Ireland indexes and located an 1825 baptismal record for a John Gillooly in the Athleague RC records. The parents were Owen and Celia. I did not find any other Gillooly baptismal records with parents Owen and Celia. Roots is a subscription site. Later this summer the National Library of Ireland plans to place all RC parish registers online for free searching. I would check the Athleague records at that time.