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Thomas J. Diener

Jun 26, 1999 - Dec 11, 2025

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On December 11, 2025, our son Thomas, was called home by his Lord and Savior Jesus Christ. Thomas was on his way home when the truck he was in was struck by a semi in Indiana. Thomas was amazing. He would jump in and help anyone. He was so smart he absorbed anything he read. He taught himself guitar and played keyboards. His first love was the drums. At age 5 he picked up a pair of drumsticks and never looked back. As a teenager he developed an interest in pipe organs. He learned and was supported by our parish music director and was given opportunities to play. Thomas started to usher at our parish as a teenager. At age 10 he discovered his interest in tornado sirens. No one knew more about the subject than Thomas. Over the years he obtained quite a collection. His parents’ basement, garage, shed, and his grandma’s garage are full. He also put one up in his backyard.
At age 16 he joined the Town of Sheboygan Fire Department as a cadet. He eventually went on to run the cadet program. Thomas made his way to Lieutenant. Thomas was very proud to be a member of the TSFD. While a senior in high school he attended MATC at night. At 18 he earned his EMT license and began running calls for the town. At 21 Thomas earned his Paramedic/Firefighter degree and was hired by the Oshkosh Fire Department. He was the second youngest ever hired. When asked what he wanted to do with his life Thomas replied, “I want to help people”.
Several years ago, Thomas and his friend Carter started Sheboygan Warning Systems. They would service and install tornado sirens though out the Midwest. If Thomas was not working at the OFD he was off working on sirens.
In Thomas’ junior year of high school, he met the love of his life, Elise. He loved Elise with all his heart. Elise was a constant support for Thomas. He loved to make her laugh. Thomas had a great sense of humor. His face would brighten when he would get someone to laugh.
Thomas had many interests, he grew carnivorous plants, and hot peppers which he made into salsa. He wrote music and often would get together with his brother Andrew and play their guitars. Whatever Thomas put his mind to he did it with passion. He devoured it and learned everything he could.
Gary and I were blessed the day Thomas was born. We will miss his smile. We will miss his daily visits to talk about things going on in his day. We will miss him just being Thomas.
Thomas is survived by his parents Gary and Eileen, his brother Andrew, the love of his life Elise, maternal grandmother Dolores Ruppel of Sheboygan, paternal grandfather Donald Diener of Sheboygan, aunts Wendy (Doug) Born of Sheboygan, Lynn (Dave) Klosterman of Mukwonago, Marie (Glenn) Seger, of Sheboygan, Jackie Diener of Milwaukee, Carrie Diener of Milwaukee, uncle Craig Diener of Wisconsin Rapids, cousins Amy Lesperance of Fox Point, Mychal (Alyse) Seger of Port Washington, D.J. (Brigette) Born of Fox Point, Eric (Jen) Klosterman of Milwaukee, Shawn (Jean) Seger of Sheboygan, Alex (Miranda Klosterman of Milwaukee and Matt Seger of Sheboygan.
Thomas was preceded in death by his paternal grandfather Gerald Ruppel and step- grandmother Kim Diener.
Family and friends may gather at St. Dominic Catholic Church, 2136 N. 21st Street, Sheboygan on Saturday December 20, 2025, from 9:00 a.m. until the time of mass at 1:00 p.m. Fr. Phil Reifenberg will officiate. Burial will take place in the Calvary Cemetery.
In lieu of flowers a memorial fund has been established in Thomas’ name.

Thomas’ family wishes to extend a special thank you to the Oshkosh Fire Department and The Town of Sheboygan Fire Department for bringing Thomas home from Indiana. The Plymouth Indiana Fire Department. The 10 surrounding Marshall County Indiana fire departments that guarded Thomas while in Indiana. They never left his side. The 8 volunteer fire departments that transferred Thomas and escorted him to the county line. The people of Marshall County Indiana who wanted to help any way they could. The sheriff and police departments that participated in Thomas’ escort home. All Fox Valley fire departments that filled in for the Oshkosh Fire Department so they could be here when Thomas returned home. A very special thank you to Ashley of the Oshkosh Fire Department.

We are so blessed for the outpouring of love and support from our family and friends. You keep us moving forward.

Visitation

Date: Saturday Dec 20, 2025
Time: 9:00 a.m. - 1:00 p.m.
Location: St. Dominic Catholic Church [map]

Mass of Christian Burial

Date: Saturday Dec 20, 2025
Time: 1:00 p.m.
Location: St. Dominic Catholic Church [map]

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Guestbook Entries SIGN GUESTBOOK

Nancy & Dave Papendieck

We are so very sorry for your loss. I am Carter's great-aunt and my heart just broke hearing of the loss of your son. There are no words to say to ease your loss, just know that even though we did not know Thomas, you are in our thoughts and prayers. He sounded like an amazing person. God bless all of you.

Frederick Strassburger

I am so sorry about the loss of such a fine young man that I had the privilege teaching him how to play the pipe organ when he was in high school. He was so full of life and I was so shocked when I saw on Facebook that he had died in that tragic accident. My thoughts and prayers go out to his family as they face a future without him.

Dianne Marshall

Thomas was a wonderful human being being and always a joy to be around. I loved seeing him engage in his passions through music and elsewhere. I know he is now watching over everyone as they grieve.

Robin and Shawn Starck

Our hearts go out to the whole family and Elise. We are praying for strength at this very difficult time. Thomas was a wonderful friend to our son Seth. He spent many hours at our home playing music and even cooking with Seth. We will deeply miss Thomas, but we are so very thankful to God for their friendship..

Nancy and David Beck

Our thoughts and prayers are with the Diener family and with Elise. Tom was a wonderful young man and a truly awesome friend to our son Brady. He will be missed immensely by Brady and their friend group. Heaven definitely has welcomed a new angel. RIP Tom.