A memorial Mass for Deacon Robert C. Riegel will be celebrated at 10 a.m. Saturday, Dec. 23, at St. Louis Abbey Church, 500 S. Mason Road in Creve Coeur.

Deacon Riegel, 90, died Dec. 7.

A St. Louis native, he attended McBride High School and St. Louis University, where he earned a bachelor's degree in chemistry. He served in the U.S. Army for three years and married Mary Lee Gieringer in 1953. They had six children. A chemist and plant manufacturer for a manufacturer, he retired in 1987.

Deacon Riegel was ordained to the Sacred Order of the Diaconate in 1991 by Archbishop John L. May. He was assigned to Mary Queen of Peace Parish in Webster Groves and served that parish until his retirement in 2005. In addition, Deacon Riegel served as the assistant director of the diaconate from 1994-97.

At Mary Queen of Peace Parish, he performed the sacramental functions of a deacon, specifically assisting at Mass, conducting wake services and attending funerals, leading Liturgy of the Word and Communion Services when needed, performing baptisms, conducting benedictions and leading Stations of the Cross. Deacon Riegel also worked extensively in a variety of parish-based ministries, especially as an advocate with the Metropolitan Tribunal, a hospital chaplain and with the homebound.

Survivors include his wife, Mary Lee Riegel; five children, Robert C. Riegel, Jr., Mary Kathleen Kerlick, Joseph C. Riegel, Mary Lee Mimi Williams, Richard T. Riegel; 11 grandchildren; and six great-grandchildren. He was preceded in death by a daughter, Susan J. Riegel.