Birth Name: Daniel Peter Masterson
Place of Birth: Long Island, New York, U.S.
Date of Birth: March 13, 1976
Danny Masterson is an American actor and disc jockey. His brother is actor Christopher Masterson, and his half-siblings are actors Jordan Masterson and Alanna Masterson, as well as Will Masterson. Danny is married to actress, model, socialite, and singer Bijou Phillips, with whom he has a daughter.
Danny’s paternal grandfather was Frank J. Masterson (the son of Patrick Masterson and Mary Mulligan). Frank was born in New York, to Irish parents.
Danny’s paternal grandmother was Dorothy Boylan (the daughter of Peter J. Boylan and Mary Josephine Mulledy). Dorothy was born in New York. Peter was the son of Irish parents, Dennis Boylan and Annie. Danny’s great-grandmother Mary Josephine was also the daughter of Irish parents, Malachy Mulledy, from Longford, and Mary Margaret Lennon.
Danny’s maternal grandfather was named Francis Bernard Nicholson. Francis was evidently the grandson of Henry Nicholson and Ella, who were born in England, and likely had Irish ancestry.
Danny’s maternal grandmother was named Helen Teresita McCormick (the daughter of Thomas J. McCormick and Maria J.).
Sources: Obituary of Danny’s paternal grandfather, Frank J. Masterson – http://freepages.genealogy.rootsweb.ancestry.com
Obituary of Danny’s paternal grandmother, Dorothy (Boylan) Masterson – http://www.legacy.com