Joseph William Kleffner

Joseph William Kleffner, affectionately known as Joe, touched the lives of many during his remarkable journey through life. Born on October 27, 1942, in St. Louis, Missouri, he was a dedicated family man whose warmth and generosity radiated to all who knew him. Joe passed away peacefully on December 20, 2025, surrounded by his loving family.

A proud graduate of St. Louis University High School, Joe furthered his education at Rockhurst University and ultimately earned his degree from the University of Missouri St. Louis. He devoted 34 years to his career at Monsanto, returning later as a contractor for over a decade, a testament to both his commitment and expertise.

Joe was a loving husband and a proud father who treasured every moment with his family. His greatest accomplishments included a beautiful partnership with his beloved wife, Kathleen, who he treated like a queen throughout their 56 years of marriage. Together they created a strong family, with four wonderful children: Judy (Ken) Reel, Tim (Kelly) Kleffner, Dan (Sandy) Kleffner, and Teresa Kleffner, each of whom carry forward his legacy of love and support. Joe was a family man to the core, who, along with his wife, instilled a strong foundation of family in his children and grandchildren that will live on for generations to come.

Joe was a proud grandfather to his grandchildren — Kenny (Sarah), Meghan, Michael, Josh (Katie), Abby (Raymond), Matthew (Brooke), Adam (Lindsey), Jacob, Ben, Grace, and Sam — and a great-grandfather to the next generation: Lilly, Kendal, Cooper, Jameson, Wesley, Lorelei, Peyton, Kylie, and Sullivan. He was always interested in their pursuits, forever ready to offer encouragement and to inquire about their dreams.

Joe found joy in cooking delicious meals for his family and rehab projects at home, along with golf, reading, photography, music, and movies. Joe was a man of few words, whose actions spoke volumes. Whether he was lending a hand to someone in need or engaging in spirited debates, he was a steady source of support and guidance.

Joe’s intelligence and love for science, particularly chemistry, were evident throughout his life, alongside an interest in technology that enabled him to share his knowledge with those around him (and he really enjoyed sharing his knowledge!). He enjoyed camping trips with his children during their formative years and later beach trips and family days spent by the pool, grilling for friends and family, creating memories that will last a lifetime.

Joseph William Kleffner is survived by his children, grandchildren, great-grandchildren, and a host of family members who will carry his memory in their hearts. He now joins his beloved wife, Kathleen. He is also predeceased by his parents, Cornelius and Vera Kleffner, his siblings, Marianne McKean and Robert Kleffner, many members of the Doherty Family, who welcomed him wholeheartedly as a member of the family, and many other extended family members, who have gone before him.

As we gather to remember Joe, we celebrate a life well-lived, filled with love, laughter, and unwavering support for those he cherished most. His spirit and legacy will continue to shine brightly in the hearts of all who knew him.

Visitation to be held on Saturday, January 24, 2026, at All Saints Catholic Church, 7 McMenamy Rd, St Peters, MO 63376 from 9:00 am until 10:00 am with a Funeral Mass to follow at 10:00 am.

In lieu of flowers, donations can be made to Loyola Academy of St. Louis. Please click the link to donate or mail donations to Loyola Academy of St. Louis, 3851 Washington Blvd. Saint Louis, Missouri 63108.