Father Sir Cornelius O'Brien MP 1782-1857
Mother Margaret Long 1793- 1839
He was a Teamster and he lived on 3 Utica Street in Boston, MA.
Dennis became a U.S. citizen in 1861. 
Name: Dennis O'Brien Event Type: Marriage Birth Date: abt 1834 Marriage Date: 19 Nov 1854 Marriage Place: Boston, Massachusetts Marriage Age: 20 Father Name: Cornelius Spouse Name: Margaret Cain Spouse Marriage Age: 19 Spouse Father Name: Michael Source Information Original data: Town and City Clerks of Massachusetts. Massachusetts Vital and Town Records. Provo, UT: Holbrook Research Institute (Jay and Delene Holbrook).
Name: Dennis O'Brien Gender: Male Birth Date: abt 1834 Birth Place: Ireland Death Date: 10 Mar 1886 Death Place: Cambridge, Massachusetts, USA Age at Death: 52 Wills and Probates: Search for Dennis O'Brien in Massachusetts Wills & Probates collection Source Information Original data: Massachusetts Vital Records, 1840–1911. New England Historic Genealogical Society, Boston, Massachusetts.
Find A Grave Memorial# 98021476 Name: Dennis O'Brien Birth Date: 1833 Death Date: 10 Mar 1886 Cemetery: Catholic Mount Auburn Cemetery Burial or Cremation Place: Watertown, Middlesex County, Massachusetts, USA Has Bio?: N URL: http://www.findagrave.com/cgi-bin/fg.cgi?page=gr&GRid=98021476&ref=acom
Have you taken a DNA test? If so, login to add it. If not, see our friends at Ancestry DNA.
Dennis is 22 degrees from John James Audubon, 25 degrees from Jacques-Yves Cousteau, 36 degrees from Gerald Durrell, 26 degrees from Dian Fossey, 25 degrees from Steve Irwin, 36 degrees from Ernest Just, 23 degrees from Ian Player, 16 degrees from Peter Scott, 35 degrees from Antoon van Hooff and 25 degrees from Marta Johnson on our single family tree. Login to find your connection.