One of the four children of the late James and Alice (Browne) DeAdder, Father James W. DeAdder was born June 30, 1927 in Lawrence and grow up next door in North Andover, a son of the town's only parish, St. Michael.

He attended local schools and on graduation from high school in 1944 he entered the United States Army. During his military service he attended both the University of Maine and Norwich University in Vermont. Returning to civilian life he completed his collegiate undergraduate career at Boston College with a B.S.B.A. degree and entered St. John Seminary. He was sent to complete theological studies in Rome, living at the Pontifical North American College. He was granted a license in sacred theology from the Pontifical Gregorian University.

The rector of PNAC, the Most Rev. Martin J. O'Connor, ordained him to the priesthood in the seminary chapel on Dec. 17, 1955. Father DeAdder returned to the archdiocese and was appointed an assistant at St. Margaret of Scotland, Beverly. He returned to the Eternal City for further studies in 1957 and was granted both a Ph.D. and S.T.D., doctoral degrees respectively in philosophy and theology from the Pontifical University of St. Thomas Aquinas -- the Angelicum.

Returning again to the archdiocese he was appointed an assistant at the Cathedral of the Holy Cross, Boston; then at St. Mary of the Annunciation, Cambridge and what would be his last parish assignment at Sacred Heart, East Boston.

In July 1964 he was appointed to the faculty of the newly created Pope John XXIII Seminary for Delayed Vocations; now Pope St. John XXIII National Seminary, Weston. He would serve at the seminary for a record 33 years, as a faculty member and as the seminary's third rector (1973-1981). In his spare time he also obtained a law degree, J.D., from Suffolk University and was a member of the Massachusetts Bar Association. On June 30, 1997 he was granted senior priest/retirement status by Cardinal Bernard Law.

He retired, initially to the family home in North Andover, and subsequently in 1999 to Regina Cleri Residence in Boston. Although retired he assisted in archdiocesan parishes among them, St. Barbara, Woburn.

Cardinal Seán P. O'Malley, OFM Cap. was to be the principal celebrant of Father DeAdder's Funeral Mass at St. Michael Church, North Andover on July 27. Msgr. Dennis F. Sheehan, Father DeAdder's successor as rector of Pope St. John Seminary and fellow faculty member with him there was to be the homilist of the Mass.

Father DeAdder's survivors include his younger siblings, all residents of North Andover, his sister, Nancy Barry and brothers Robert and Donald.

Father DeAdder was buried in Holy Sepulchre Cemetery, North Andover.