That's great Karla - the Mary Hynes connection does sound convincing.
The other children to John Hehir & Bridget Dooley are:
Name:Bridget HehirDate of Birth:07-Nov-1860
Date of Baptism:08-Nov-1860Address:CrushoeParish/District:KINVARAGender:FemaleCountyCo. Galway
Denomination:Roman Catholic
Father:John HehirMother:Bridget DoolyOccupation:
Sponsor 1 /
Informant 1:Thomas HYNES Sponsor 2 /
Informant 2:Bridget Kilkelly
Name:Martin HeherDate of Birth:13-Oct-1863
Date of Baptism:15-Oct-1863Address:CarroneenParish/District:KINVARAGender:MaleCountyCo. Galway
Denomination:Roman Catholic
Father:John HeherMother:Bridget DooleyOccupation:
Sponsor 1 /
Informant 1:Patrick Not Recorded Sponsor 2 /
Informant 2:Bridget Heher
Name:John HeherDate of Birth:26-Jun-1866
Date of Baptism:28-Jun-1866Address:CrushuaParish/District:KINVARAGender:MaleCountyCo. Galway
Denomination:Roman Catholic
Father:John HeherMother:Bridget DooleyOccupation:
Sponsor 1 /
Informant 1:Thomas Kilkelly Sponsor 2 /
Informant 2:Mary Farrell
Name:John HehirDate of Birth:20-Jun-1866
Registration Date:
Address:HehirParish/District:KINVARAGender:MaleCountyCo. Galway
Denomination:Civil Parish / District
Father:John HehirMother:Bridget DoolyOccupation:Labourer
Sponsor 1 /
Informant 1:John Hehir
Name:John HehirDate of Birth:04-Nov-1869
Registration Date:
Address:CrushuaParish/District:KINVARAGender:MaleCountyCo. Galway
Denomination:Civil Parish / District
Father:John HehirMother:Bridget DoolyOccupation:Labourer
Sponsor 1 /
Informant 1:Bridget Hehir
There are 3 Johns - the custom was to name another son for a previous one which had died. However, the last John was born only two months after your Michael...?!
The address where it is given seems to vary from Chrushua to Crushoe to Carroneen but the only one which came up in a google search was CarNoneen.
The Tithe Applotments (free online) have 7 Hehirs in Galway 1826-33:
Surname Forename Townland/Street Parish County Year
HehirMichlBallygerane Isertkelly Galway1833
HehirDennisKnocktroe Or Woodville Bog IsertkellyGalway1833
HehirEdmondKnocktroe Or Woodville Bog IsertkellyGalway1833
HehirJohnLavalla Connor KilcolganGalway1826
HehirOwenEmlagh Killogilleen Galway1828
HehirJamesRue Kilmacduagh Galway1826
HehirJamesRue Kilmacduagh Galway1826
Even better, the 1821 Irish Census (free online http://www.census.nationalarchives.ie/) has 39 HehErs in Galway; there are several Michaels and Johns and Athenry is one of the parishes. If you've never heard the song Fields of Athenry you might like to have a listen. The irish sing it at big football games and it brings tears to my eyes just thinking about it - but I'm nearly as old as your aunt (73)!
Couldn't find any Bryan Hehirs in Galway baptisms but there are lots of Michaels & Johns including some from Kinvara.
If we can sort out which of the above are yours it will give you a few addresses to visit during your trip
Col