Carmella T. DeCosty was born in Rome, New York, the eldest child of Fiore and Josephine Cosimeno DeCosty. After graduating from the Academy of the Holy Names High School she entered the Sisters of the Holy Names of Jesus and Mary.

After her profession of vows, she was assigned to the newly established Sacred Heart Academy in Winchester, Virginia, where she taught first grade for five years. After making her final profession in 1962, she was missioned in the Diocese of Albany, New York, and was assigned to teach first grade at St. Thomas the Apostle School in Delmar. In 1969 she was assigned to Our Lady of Perpetual Help School in Opa Locka, Florida, as principal. In 1976 she was appointed Assistant Superintendent of Schools for the Archdiocese of Miami, a position she held until 1985 when she was appointed the first Director of Education for the newly established Diocese of Venice. Since 1990, Sister Carmella has served as Executive Assistant to the Bishop of Venice in Florida and at the present time also serves as Assistant Provincial for the Sisters of the Holy Names of Jesus and Mary of the New York Province.

She holds a BA in Elementary Education from Marywood College, Scranton, Pennsylvania; an MA in Religious Studies from Barry University, Miami, Florida; and is certified in Administration by the State of Florida.

Sister Carmella will begin her ministry as Administrator of Our Lady of Perpetual Help Retreat and Spirituality Center in September 1999.

She has a sister and brother who live with their families in Rome, New York, and another brother residing in St. Peter, Missouri.