John Mertz Sr., a beloved figure in the Seguin community, passed away peacefully on October 6, 2025, at the age of 74. Born on February 19, 1951, in Seguin, Texas, John spent his entire life in the town that he cherished so deeply.
John was a devoted husband to his wife of 52 years, Cecilia Lopez Mertz. Together, they raised a loving family that included their children Jesse A Valdez (Lupe), Lisa A Rodriguez-Mertz (Irma), Rebecca M McHaney (John), Rachel M Leal (Andrew), and Johnny Mertz Jr (Carolyn). He took pride in being a grandfather to his 16 grandchildren and a great-grandfather to 25 great-grandchildren, creating lasting memories with each generation.
He is also survived by his siblings MaryLou Deardorff (Don), Henry Mertz Sr. (Joann), Sylvia Sanchez (Jesse), Melinda Villareal, Berta Soria, and Willie Mertz Jr (Petra). John was a pillar of support and love for his family, always relishing the times spent together, particularly while watching the Cowboys play and barbecuing—two of his favorite pastimes.
John is preceded in death by his father, Willie Mertz Sr., and his mother, Mary Lou Mertz Hinds, who instilled in him the values of hard work and community spirit that he carried throughout his life.
The family will be honoring John's life with pallbearers including Nat Rodriguez Sr, Mike Rodriguez, B.J Rodriguez, Oscar De La Cruz, Chris Oates, and Timothy Hardeman. Honorary pallbearers are Henry Mertz Sr, Willie Mertz Jr, and Cesario Guadarrama III.
The family wishes to express special thanks to the staff of Gifted Hearts Hospice for their compassionate care during John's final days. He will be profoundly missed by all who knew him, and his legacy will live on through the countless memories shared with his family and friends.
The family will receive condolences on Monday, October 13, 2025 at Palmer Mortuary from 4pm to 8pm. The recitation of the Holy Rosary will begin at 6pm.
A funeral mass will be celebrated on Tuesday, October 14, 2025 at 10:30am at Our Lady of Guadalupe Catholic Church and interment will follow at Our Lady of Guadalupe Catholic Cemetery.
To plant trees in memory, please visit the Sympathy Store.
1116 N Austin St, Seguin, TX 78155

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