
Mr. Grau was a systems engineer at Prometheus Security Group Global. He was a United States Marine Corps veteran and a United States Army veteran. Mark was a member of St. Joseph Catholic Church, Freeburg, IL. He loved golf, hunting, and all sports. The Chili Cookoff was one of his favorite events. Mark was a loving and supportive father, brother, grandpa, and uncle. He was the kind of man/father you could always count on.
He was preceded in death by his parents, Walter and Golda, nee Harris Grau.
He is survived by three sons, Jason (Amie) Grau, Jake (Brettney) Grau, and Joseph (Brooke) Grau; a daughter, Clair Wiechert; eight grandchildren, Jasmine, Briley, Kenleigh, Kaislee, Greyson, Emma, Mikey, and Maverick; two sisters, Joyce A. Weber of St. Louis, MO, and Debbie S. (Dale) Wilson of Belleville, IL; three brothers, Allen L. (Debbie) Grau of Haubstadt, IN, Jack J. Grau of Lenzburg, IL, and Jim W. (Cindy) Grau of Fayetteville, IL; and many nieces and nephews.
Memorials may be made to the Wounded Warrior Project. Condolences may be expressed to the family online at www.rennerfh.com.
Visitation: Friends may visit from 4 to 8 p.m. Thursday, June 1, 2023, and from 9 to 10 a.m. Friday, June 2, 2023, at St. Joseph Catholic Church, Freeburg, IL.
Funeral: A Mass of Christian Burial will be held at 10 a.m. Friday, June 2, 2023, at St. Joseph Catholic Church, Freeburg, IL, with Fr. Von Deeke and Deacon Corby Valentine officiating.
Burial with military honors will be at St. Joseph Catholic Cemetery, Freeburg, IL.