Dennis “Sully” G. Sullivan, 72, of Wisconsin, passed away on Tuesday, August 18, 2026, following a courageous two-year battle with esophageal cancer.
Sullivan was remembered as a devoted husband, father, grandfather, brother, uncle, and friend whose larger-than-life personality, humor, generosity, and deep love for his family left a lasting impression on everyone who knew him.
Remembering Dennis “Sully” Sullivan
Dennis was born on November 28, 1953, in Milwaukee, Wisconsin, to Bob and Cathy Sullivan. He grew up in Milwaukee and graduated from James Madison High School in 1972.
A gifted athlete, Dennis excelled in basketball, football, and especially baseball. His talent as a catcher earned him a scholarship to the University of Wisconsin-Madison, reflecting his lifelong passion for sports.
For nearly 40 years, Dennis worked as a welder and took great pride in the life he built through dedication and hard work.
Sports remained an important part of his life. He was a passionate supporter of Wisconsin teams, enjoyed fantasy football, and loved the friendly conversations and banter that came with being around fellow sports fans.
A Passion for Music
Music was another important part of Dennis’ 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 with the band or simply listening to his favorite songs.
He also shared his appreciation for music with his children and grandchildren, creating another lasting connection across generations.
A Devoted Husband and Family Man
Above everything else, Dennis treasured his family.
He was married to his wife, Pauline Sullivan, for 45 years. Together, they raised their family and built a life centered around love, laughter, and togetherness.
Dennis 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 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.
Life in Menomonee Falls and Germantown
Dennis 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.
Dennis took great pride in his homes and spent countless hours caring for his yard and creating beautiful gardens. His family remembered him as someone who made every place he lived warm and welcoming.
In retirement, one of his greatest joys was simply being present for the people he loved.
He regularly attended his children’s and grandchildren’s activities, cheering them on at soccer, baseball, basketball, dance recitals, school plays, and other events.
If one of his children or grandchildren was participating, Papa was there.
Dennis Sullivan’s Legacy
Dennis will be remembered for his unmistakable personality, sense of humor, love of sports, passion for music, strong work ethic, and devotion to his family.
His friendships were also an important part of his life. People who met him through local athletic events and other community activities remember his warmth and memorable personality.
For his family, however, his greatest legacy will always be the love and pride he showed them.
He was the husband who built a 45-year marriage, the father who supported his children, and the grandfather who made sure his grandchildren knew how proud he was of them.
Dennis “Sully” Sullivan Funeral and Memorial Service
Visitation for Dennis “Sully” G. Sullivan will be held on Thursday, August 27, 2026, at 2:00 p.m. at Good Shepherd Catholic Church, N88W17658 Christman Rd., Menomonee Falls, Wisconsin 53051.
A Mass will follow at 4:00 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 Dennis’ life.
Those who knew and loved Dennis will gather to share memories and honor a man whose family, friendships, sports, music, humor, and generosity made him deeply cherished.
Dennis “Sully” G. Sullivan will be remembered with love and gratitude by his family, friends, and everyone whose life he touched.
May he rest in peace, and may his loved ones find comfort in the many memories of the remarkable life he shared with them.