In loving memory of Sister Mary Brian Costello, RSM

In loving memory of Sister Mary Brian Costello, RSM

The Mother McAuley community is deeply saddened to share that Sister Mary Brian Costello, RSM passed away peacefully on May 22 at Mercy Circle. 

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Visitation will be held from 4 to 7:30 pm on Monday, May 29, at Mercy Hall, 10044 S. Central Park, Chicago, IL.  and from 9-10:15 am on Tuesday, May 30.  A Remembering service will be held at 6:30 pm Monday.

Mass of Christian Burial will be on Tuesday at 10:30 am at Mercy Chapel, 10044 S. Central Park, Chicago.  Interment at Holy Sepulchre Cemetery.  

More about Sister Brian

Sister Brian spent over 80 years as a Sister of Mercy serving in a variety of educational ministries. In all of these settings her primary focus was preparing young women for lives as competent Christian leaders in a rapidly evolving world, making them “Future Ready”. 

Sister Brian arrived at Mother McAuley in 1959 and served in a variety of roles including an English teacher, Curriculum Director, and Principal (1970-1973). She has also served as the Director of the Big Shoulder Campaign for the Archdiocese of Chicago and Chief of Staff and Superintendent of Schools in the Chicago Archdiocese (1984-1991). 

Sister Brian was named the Executive Director of Mother McAuley for the 1970-71 school year, and was renamed principal during 1972-73. During these years Sister Brian sought innovative ways to integrate the liberal arts and critical analysis skills into all areas of the curriculum. As Sister Brian observed, “The Liberal Arts of learning and communication are particularly effective in developing a woman’s way of learning.” In addition to innovative content, Sister Brian recognized the possibilities of emerging technologies and opened a television studio to allow master teachers to reach into each classroom. She also introduced advanced placement classes allowing students to test out of some college level courses.

From 1973 to 1979, Sister Brian served on the leadership team of the Sisters of Mercy, Chicago Province where she had responsibility for the Sisters’ apostolic works and planning for the future of the Sisters of Mercy education and other ministries.

In 1979, Sister Brian joined the Planning Team at the Archdiocese of Chicago School Office. Then in 1983, Cardinal Joseph Bernardin named her the first woman and non-cleric Superintendent of Schools for the Archdiocese with oversight responsibility for three hundred seventy-five schools. The plan also led to the creation of The Big Shoulders Fund to assist center city schools.  Sister assisted Cardinal Bernardin in establishing the Fund and served on the Fund’s executive committee.  

In 1987, she was awarded the first Catherine McAuley Leadership Award at the annual Celebration Gala. This award is one of Mother McAuley’s highest honors, recognizing individuals who have demonstrated a deep level of commitment, loyalty, and service to the school. 

In 1989, Cardinal Joseph Bernardin named Sister Brian Chief of Staff, a position she held until his death in 1996, and for an additional year under Cardinal George. In this role, she coordinated and directed the activities of the Cardinal’s office, including his national and international activities and communications. She was also on the Cardinal’s senior administrative team. 

In 1993, she was awarded the Harold W. McGraw Jr. Prize in Education for her outstanding work to support education in the cities poorest and most vulnerable communities. Her work included establishing summer learning centers for economically disadvantaged children and developed innovative learning programs for preschoolers, including children with learning disabilities or children in need. 

Sister Mary Brian formally retired in 1997, but remained active on many boards and committees.

She was inducted into the first McAuley Hall of Honor in 2013, a prestigious honor bestowed upon a member of the McAuley community whose story reinforces the belief that McAuley's influence provides the foundation to achieve extraordinary things. 

McAuley continues to honor her legacy by bestowing the prestigious Sister Brian Costello Award to a senior each year. The recipient of this scholarship has the honor of speaking to her classmates and their families at the Baccalaureate Mass. 

In the summer of 2022, McAuley named the Sister Brian Costello, RSM Learning Resource Center in dedication to our former principal.

Sister Brian received her B.A. from Saint Xavier University, her M.A. from the University Notre Dame and did post graduate work at Loyola University, Northwestern University, and the University of Massachusetts. She received Honorary Doctorates from Saint Xavier University, Felician College, Loyola University, and Holy Cross College.

“McAuley is very much a part of the life of the Sisters of Mercy. I’m a Sister of Mercy; it’s my identity. Once you’re in a school, become part of it and believe in what it’s doing, you stay with it. You don’t leave.” - Sister Brian

Sister Brian will be forever a part of McAuley, in our hearts and in our minds. 

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