On Nov. 4, 1938, twin girls were born to Genevieve (Kues) and Leo Markus in their family home in Aviston, Illinois. As she was premature and very fragile, Joan was baptized conditionally by her grandmother on the day she was born. Both girls were then baptized on Nov. 6, 1938, at St. Francis of Assisi Church and given the names of Joan Catherine and Carol Catherine. Five girls and one boy were raised on the family farm in Aviston where the parents’ care of the land and deep love of God and the Church were passed on to their children. Joan’s twin sister, the late Sister Carol (Miriam Gabriel) and a younger sister, Theresa (Miriam Raphael), also entered the School Sisters of Notre Dame (SSND).

Joan attended St. Francis of Assisi grade school where she was taught by the School Sisters of Notre Dame. Attracted to religious life by the dedication, prayer, lifestyle and service of her teachers, Joan transferred from Aviston Community High School to the Aspiranture at Sancta Maria in Ripa in St. Louis in her senior year.

Joan and her twin, Carol, received the candidate’s bonnet at their home parish in Aviston on Aug. 29, 1956. Joan was received into the novitiate on July 30, 1957, and given the name Miriam Michael. She professed first vows on July 31, 1958, and final vows on July 31, 1964. Later, she returned to her baptismal name.

Sister Joan earned a bachelor’s degree in theology from the former Notre Dame College in St. Louis in 1961, a master’s degree in elementary administration from Southeast Missouri State University in 1972 and a master’s degree in religious studies from Saint Louis University in 1987. She also received a certificate in justice and peace studies from Maryknoll School of Theology in New York in 1985 and a certificate in pastoral care from Aquinas Institute in St. Louis in 2004.

Sister Joan was a teacher for her first 11 years of ministry. She taught at St. Dominic Savio in St. Louis; St. Peter in Belleville, Illinois; and St. Charles Borromeo in St. Charles. She then became a principal at St. Henry in Belleville; St. Peter in Jefferson City; and Santa Isabel in Los Angeles.

She served two years as the coordinator of education for the former St. Louis Province. This was followed by two years as the director of religious education at St. Paul in Highland, Illinois.

In 1982, she began a six-year term as the coordinator of social concerns for the former St. Louis Province. During the summer months, she coordinated the ACCS (Aid to Cross-Cultural Service) and GAAP (Global Apostolic Awareness Program) programs and experienced the plight of the poor in Honduras and Bogota, Colombia.

Beginning in 1988, she served as the director of religious education in the Belleville Diocese for five years and the director of education and formation in the San Angelo, Texas Diocese for the next 11 years. Following a sabbatical, she was asked to become the administrator and local leader at the Academy of Our Lady in Chicago. During this time, she assisted the sisters in their transition to Marian Village, a retirement residence in Homer Glen, Illinois.

In 2007, she was called to serve as the provincial leader of the former St. Louis Province. During her term, she assisted in the formation of the Central Pacific Province in 2011. She then served for two years as the secretary to the General Superior in Rome. Returning to the U.S., she became the coordinator of pastoral care and director of spiritual care at St. Joseph Hospital in Breese, Illinois. In 2018, she returned to Belleville as a retreat/spiritual director, while also serving as the area coordinator for the SSND associates.

As her health failed, Sister Joan was missioned to Anna House in 2022.

Sister Joan was preceded in death by her parents, Genevieve and Leo Markus, her brother, Richard, and her twin sister, Sister Carol Markus, SSND.

Sister Joan was a gifted, prayerful and compassionate person. Her love of community and concern for the individual were very evident in her life. She expressed the desire to be remembered as “a person who cared about the marginalized and worked steadfastly for justice, especially for women in the church by empowering them through theological education and formation.”

Sister Joan donated her body to Saint Louis University School of Medicine.