Julie, the vast majority of Irish registrations are Gately, rather than Gatly, Gateley, or Gatley. Of those, nearly all are from Roscommon. Here are two possibles for your ancestor. The names are in Latin, so James is son of Bernard Gately and Mary Kelly, or of James and Ann Gately. Hope you are lucky!
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GATELY, Jacobus Christening
Gender: Male
Christening Date: 15 Jun 1864 Recorded in: Dysart, Roscommon, Ireland
Collection: Roman Catholic
Father: Bernardo GATELY
Mother: Maria KELLY
Source: FHL Film 989755 Dates: 1850 - 1881
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GATELY, Jacobus Christening
Gender: Male
Birth Date: 2 Jun 1866
Christening Date: 17 Jun 1866 Recorded in: Dysart, Roscommon, Ireland
Collection: Roman Catholic
Father: Jacobo GATELY
Mother: Anna GATELY
Source: FHL Film 989755 Dates: 1850 - 1881
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