Robert L. Sainz, age 75, passed away peacefully at his home on December 1, 2025, surrounded by the love of his family. Rob’s life was rooted in devotion to the people he cherished most. He is survived by his beloved wife of 32 years, Mary “Margaret” Sainz (nee Boyd), who was his constant companion.
Rob was a devoted father to his children from his previous marriage with (Mary Jost): Elizabeth Sainz (Michael Pittman), Katherine Sainz (Mark Detsky), and Joseph (Mackenzie) Sainz. Nothing brought him more joy than being “Grandpa Rob” to his adored grandchildren: Oscar and Josephine Pittman; Miles and Leo Detsky; and Rosalie and Maria Sainz.
Family meant everything to Rob, and he remained a caring brother to Claudia (the late Bill) Andrews, Beverley (Barne) Ploch, and Mary Beth (the late Sam) Imperiale. He was preceded in death by his parents, Russell J. and Mary J. (nee Hurley) Sainz, and his brothers Russell and James Sainz. Rob was also a loving brother-in-law, cousin, uncle, and friend who could always be counted on for support, humor, or simply a listening ear.
Rob’s family grew even larger with Margaret, and he welcomed her children David Anderson and Katherine DeSantis into his heart as his own. He cherished their children as well – Jonathan Anderson and Carlin Starr; Anthony DeSantis; and Nina (Shawn) Vinson – and delighted in becoming a great-grandfather to Vivian Rose DeSantis, Grayson Anderson, and Alina Vinson.
Rob grew up in Florissant, attending Our Lady of Fatima Grade School and graduating from McCluer High School in 1969. He continued his education at the University of Missouri – St. Louis, where he earned his bachelor’s and master’s degrees in education, both cum laude. His love of learning led him to pursue a PhD at St. Louis University, which he nearly completed.
Guided by faith, Rob was a member of St. Teresa of Avila Catholic Church in Carlyle, IL, and previously St. Mary’s Catholic Church.
Rob dedicated his career to nurturing and educating children. He served as principal at Carmen Trails and Hodge Elementary Schools and later as an adjunct professor at McKendree University. Even in retirement, his commitment didn’t fade – he worked as a para-educator in the Carlyle school district, drove a school bus, and volunteered countless hours tutoring children with special needs. Teaching was never just a job; it was his calling.
Outside of work, Rob embraced life with enthusiasm. He loved motorcycle rides, boating, and camping, and he was known for his unforgettable sense of humor – especially his mischievous streak when it came to practical jokes. At home, he found peace with a cat curled up on his lap.
Above all else, Rob’s greatest joy and proudest legacy was his family. He had a special gift for creating community wherever he went – whether with his motorcycle club, fellow bus drivers, coworkers, or parish family. His warmth, generosity, and genuine care made everyone feel like part of his extended family.
In one final act of kindness, Rob donated his body to St. Louis University, continuing his lifelong dedication to learning and helping others.
A Memorial Mass will also be held in Carlyle, IL, at St. Teresa’s of Avila at 18021 Marydale Rd, Carlyle, IL 62231, at 11:00 am on December 12, 2025. A Celebration of Life for family and friends will be held from 12:00 PM to 3:30 PM on Saturday, January 17, 2026, at St. John House at 510 West Ave, Eureka, MO 63025. In lieu of flowers, donations may be made to the Michael J. Fox Foundation for Parkinson’s Research. Online condolences may be shared by visiting his memorial page at www.ZierenFuneralHome.com. For more information, please contact Zieren Funeral Home.
