Reverend Edmond M. Derosier was born in Peabody, MA on September 25, 1947 as an only child of Gertrude and Edmond C. Derosier. His love of animals had him considering becoming a veterinarian, he answered his true calling. He studied at St. John Seminary and was ordained to the priesthood on May 19, 1973 by Humberto Cardinal Medeiros.
Fr. Derosier worked as a pastoral associate in St. John, Swampscott, MA; Our Lady Comforter of the Afflicted, Waltham, MA; and St. Thomas, Jamaica Plain before becoming a pastor of St. Anthony, Shirley on June 7, 1995. He was in charge of rebuilding the church after a devastating fire. A new parish hall was also built at that time. On June 1, 2006 he became the pastor of St. Mary, Ayer.
In 2018, these two churches became the Nashoba Valley Catholic Collaborative under the continued direction of Fr. Derosier. He is the Chaplain for the Shirley police and fire departments.