Descendants of William O'Brien and Mary Sexton

Profile manager: Gavin O'Brien [send private message]

The main goal of this project is to add well-sourced WikiTree profiles for all descendants of William O'Brien, who came to Boston, Massachusetts, from Watergrasshill, County Cork, Ireland, in 1851. He had 6 children who joined him in Boston. Other goals include researching the O'Brien family in Ireland, solving family mysteries, and using DNA to find possible ancestors and descendants.

If you are a descendant of William O'Brien and interested in joining the project, please contact the project leader, Gavin O'Brien.

Current Tasks

1. I (Gavin) am adding biography text and citations from my existing tree. 10 Mar 2021: finished main profiles through William's grandchildren
2. Edit existing profiles to add any details you have or are willing to find.
3. Create missing profiles for any children mentioned in the child list of the parent's profile.
4. Locate living descendants to: fill in missing biography details, provide photographs and stories, see if they are interested in collaborating on research. Use either traditional research or DNA matches, if you've taken an autosomal DNA test.
5. Edit profiles of spouses of direct line descendants who only have imported GEDCOM facts.
6. Add missing parents/ancestors of spouses to try and connect us to the "world tree."
7. Consider taking a Y-DNA test if you are a male and a direct male-line descendent of William O'Briens son, Michael O'Brien.
8. Consider taking a mitochondrial DNA test (mtDNA) if you are a male or female descendant of Mary Sexton's direct female line.
9. Take on one of the family mysteries below.

Family Mysteries

1. William O'Brien probably came from the town of Watergrasshill in County Cork, Ireland. What can be found out about his family in Ireland? Can the O’Brien ancestors be traced further back? When and how did a male member of the Barry family acquire the O’Brien surname?
2. Mary Sexton has unknown parents. She did not accompany her husband William to America, or else had died before his departure from Ireland.
3. Ann O'Brien seems to have come to America later than the rest of her family members. What became of her husband Michael Dailey and did she have any children with him in Ireland?
4. John O'Brien does not have a definitive arrival date in the U.S. It must have been sometime prior to his marriage in Boston on 20 November 1853. Look for naturalization records.
5. John J. O'Brien owned a frame shop in Boston. What became of the shop after he retired? He last listed his profession as a picture-frame manufacturer in 1916. The 1920 census lists his profession as "none."

O'Briens in Ireland

O'Briens in Boston

Family Cemetery Plots

See also the O'Brien "virtual cemetery" on Find a Grave: https://www.findagrave.com/virtual-cemetery/1084932

DNA Evidence