Sister of Christian Charity Mary Lawrence Cassidy passed away on May 19, 2026, at Mallinckrodt Convent, Mendham, New Jersey. Helen Theresa Cassidy, the only child of John L. and Mary E. (Gerety) Cassidy, was born on November 15, 1934, in New York City.

During her grade school years at St. Rita’s, Bronx, NY, Helen contracted polio and was in critical condition, paralyzed from the neck down. The doctor told her that she would never walk again, but with the help and prayers of family, friends, and acquaintances and the expert therapy she received through the Sister Kenny Foundation (now known as the Courage Kenny Rehabilitation Institute), Helen gradually regained her mobility except for a slight limp.  Helen graduated from St. Rita's School in 1946. She was taught by the Sisters of Christian Charity at Cathedral High School (Immaculate Conception Extension) in the Bronx.  

After a short time with the Franciscan Sisters of the Sacred Heart in Illinois, Helen was employed as an Assistant Buyer in a department store, then as a bookkeeper for a bank.  On September 2, 1954, she began her Candidacy at the Motherhouse in Mendham and was invested on August 21, 1955, receiving the religious name Sister Mary Lawrence. She made her First Profession on August 21, 1957, and her Final Profession on August 20, 1963.

Sister Mary Lawrence served as a grade school teacher for over thirty years – in Wilkes-Barre, Philadelphia, Harrisburg, Allentown, Reading, and Mountain Top (all in Pennsylvania); and in Florham Park, Elizabeth, Netcong, Newton, Rockaway and Jersey City (all in New Jersey).  During this time, Sister earned her Associate in Religious Arts from Assumption College for Sisters, Mendham (now in Denville, NJ).

Later, Sister served as Assistant to the SCC Provincial Treasurer in Mendham and as a Bookkeeper at Holy Spirit Hospital, CampHill, PA.  Furthering her education, she graduated from the School of Bookkeeping and Accounting at the Professional Career Development Institute.  

Sister served as the Treasurer of Assumption College for Sisters and as part of the office staff at Morris Catholic High School, Denville before moving to Holy Family Convent, Danville, PA, to assist with driving until her retirement.  In May 2018, she was among the Sisters who moved to the new Motherhouse in Mendham, where she took part in the ministry of prayer and presence until her death. 

Sister Mary Lawrence is survived by the Sisters of Christian Charity and her close friends. She was predeceased by her parents.

Visitation will be held in the Chapel of Mary Immaculate at the Motherhouse in Mendham on Thursday, May 21, beginning at 1:30 p.m. with Vespers being prayed at 4:30 p.m. The Liturgy of Christian Burial will be celebrated at the Chapel of Mary Immaculate on Friday, May 22, at 1:30 p.m. and will be livestreamed at sccus.org. Interment will follow at Holy Cross Cemetery on the grounds of the Motherhouse. In lieu of flowers, donations may be made in memory of Sister Mary Lawrence Cassidy to the Sisters of Christian Charity, 350 Bernardsville Road, Mendham, NJ 07945, or at sccus.org.