Dennis “Sully” G. Sullivan Obituary, MENOMONEE FALLS, Wis. — Dennis “Sully” G. Sullivan, 72, of Wisconsin, died Tuesday, August 18, 2026, following a courageous two-year battle with esophageal cancer. He was remembered as a devoted husband, father, grandfather, brother, uncle and friend whose larger-than-life personality and love for family left a lasting impression on those who knew him.
Sullivan was born November 28, 1953, in Milwaukee, Wisconsin, to Bob and Cathy Sullivan. He grew up in Milwaukee, where he developed the strong work ethic, sense of humor and devotion to family that would remain defining parts of his life. He graduated from James Madison High School in 1972 and was a gifted athlete, excelling in basketball, football and especially baseball. As a catcher, his talent and dedication earned him a scholarship to the University of Wisconsin-Madison.
For nearly 40 years, Sullivan worked as a welder and took pride in the life he built through hard work. He was also passionate about sports, particularly Wisconsin teams, and enjoyed fantasy football, friendly banter and spending time with friends. His connection to local athletics was remembered by those who knew him through Menomonee Falls Athletic events, including one friend who shared that they first got to know Sullivan about 10 years ago while taking photographs at the events.
Music was another important part of Sullivan’s life. For more than a decade, he played drums with The Flunk Band, which performed 1960s rock-and-roll music. His love for the music of his youth remained strong throughout his life, whether he was performing behind the drum kit or listening to his favorite songs. He also passed that appreciation for music on to his children and grandchildren.
Above all, Sullivan treasured his family. He was married to his wife, Pauline Sullivan, for 45 years and was the proud father of Kelsey (Steve) Sperl, Deanna (Joseph) Orlofski and Mallary (Andrew) Sedlmeier. He was also a beloved Papa to seven grandchildren: Isla, Skylar and Sully Sperl, Abram and Hank Orlofski, and Luca and Laney Sedlmeier. He is also survived by his siblings Gary (Lora) Sullivan, Kim (John) Hagie and Kelley (Dave) Schroeder, along with nieces, nephews, extended family members and dear friends. His parents, Bob and Cathy Sullivan, preceded him in death.
Sullivan and Pauline made their home in Menomonee Falls for 38 years while raising their family before beginning a new chapter in Germantown five years ago. He took great pride in his homes and spent countless hours caring for his yard and creating beautiful gardens. His family described him as someone who made every place he called home warm and welcoming, and his greatest joy in retirement came from being present for the people he loved.
Sullivan was especially devoted to supporting his children and grandchildren. He could often be found cheering them on at sporting events, performances and activities, whether it was soccer, baseball, basketball, dance recitals or school plays. His family remembered that if one of his children or grandchildren was involved, “Papa” was there, proud and fully invested. He will be remembered for his unmistakable presence, love of sports, sense of humor, passion for music and, most of all, the profound pride and unwavering devotion he showed his family.
Visitation for Dennis “Sully” G. Sullivan will be held Thursday, August 27, 2026, at 2 p.m. at Good Shepherd Catholic Church, N88W17658 Christman Rd., Menomonee Falls, Wisconsin 53051. Mass will follow at 4 p.m. After the service, family and friends are invited to The Hot House Tavern, N88 W16631 Appleton Ave., Menomonee Falls, for food, drinks and a celebration of Sullivan’s life. Those who knew and loved Dennis will gather to share memories and honor the legacy of a man whose family, friendships, sports, music and generosity made him deeply cherished.
