Hi,
You are probably on your Irish trip at the moment.
Unfortunately your search is like looking for a needle in a haystack!
Do you know when James arrived in the US? Have you checked the ship's manifests on Ancestry? You might be lucky and find that a parent 's name and address as next of kin may be found on them.
Have you been able to access James' Naturalization records? Often on these records the location of the townland area and the parents names were recorded on these documents. Sometimes they might just say Donegal.
Did you have any very close DNA matches that currently live in Donegal? Have you contacted any of them as they might have information on the area/parish your Breslan/Sheerin families came from.
Headstones can be another valuable resource in trying to find Ancestors however in the early to mid 1800's most of the poorer people would mark a family grave with a simple stone. Later on when their family who emigrated to the US would pay for a lovely headstone to be put up in their memory.
Some Headstone sites
www.igp-web.com/headstones index searchable
www.historicgraves.com also searchable
www.findagrave.com/donegal As you already know these surnames are so common in Donegal it is so difficult to pinpoint the parish/district where James came from.
Donegal is a stunning area and even if you don't find your relations there you will still have a wonderful time.
Best of luck,
Mary
