I have been researching my new daughter-in-law's ancestry for the past year. Her Garrity line goes back through three generations of Hugh Josephs to a Thomas J.
According to his and his son's marriage license he was born in Ireland on 21 Dec 1861.
Is this perhaps your young Thomas arriving in Philadelphia ca. 1864 with his father Hugh?
Al Achtert
aachtert@verizon.net