Hello again Judy!
This side of your family is going to be difficult. The Clifden RC records start in 1838 which is good since many parishes in the west of Galway start around 1870. When I search the subscription site Roots Ireland I can only find three Trewel/Truel baptismal records in Clifden RC parish all for the same family (father was Patrick) and none were named Anthony.
I checked the 1901 census for Co. Galway and ther were no Truel or Trewel records for all of Galway.
I'm wondering if the name was actually Toole. See the record I found below. Have your heard any connections to Toole?
Name:Anthony TooleDate of Birth:
Date of Baptism:18-Aug-1853Address:Not RecordedParish/District:CLIFDENGender:MaleCountyCo. Galway
Father:John TooleMother:Anne JoiceOccupation:
Sponsor 1 /
Informant 1:Peter FahertySponsor 2 /
Informant 2:Winifred Malley