Cooper Liam Sullivan

Cooper Liam Sullivan was born to Sean Brian Sullivan and Tracie Laine Hefner in March 2001. His two older siblings, Connor and Caroline, welcomed him into the world and adored him from the start. It's commonly known among the family that Cooper's language abilities developed a little later, as Connor and Caroline often advocated for and spoke on behalf of their little brother.

From his earliest days, Cooper was a child filled with energy and an adventurous spirit. As a toddler, he was king of the Post Road Dunkin' Donuts in Fairfield, CT where his mom would bring him every day to have a few munchkins and mingle with the other regulars. He was a community favorite at that store.

Growing up on Woods End Road, Cooper was involved in nearly every game or activity that happened with his peers on the street. He would bounce from neighbor's house to neighbor's house, beginning early in the morning and playing late into the evening.

Cooper attended Riverfield Elementary School and performed well in every way except for a few minor setbacks in art class. Cooper learned to play the saxophone in fourth grade and kept with it through high school.

In his elementary school years, he began playing Little League Baseball, Wakeman basketball, and even tried his foot at Rec soccer.

Cooper's father, Sean, was diagnosed with cancer when Cooper was 10 years old. Witnessing his father's experience with illness for over half his life enabled him to face anything that came his way with grace and love.

As an infant, Cooper was baptized in the Catholic Church. In July 2013, at age 12, Cooper was baptized as a member of the Church of Jesus Christ of Latter-day Saints along with the rest of his immediate family and remained a faithful follower of Jesus Christ throughout the remainder of his life.

Cooper attended Roger Ludlowe Middle School and Fairfield Ludlowe High School. He would have graduated in the class of 2019 there, but as the last child living at home, he was subject to his parents' move to Utah in the summer of 2017.

In August 2017, Cooper started his junior year of high school at Davis High School in Kaysville, UT. He graduated in the class of 2019.

During Cooper's senior year in Utah, he began working at the local Home Depot in Layton. He became a star employee, learning in-depth knowledge to help customers in each of the various store departments. He also developed many beautiful friendships with his coworkers of all ages and backgrounds.

Cooper transferred to the Lindon store location in August 2019 when he enrolled at Utah Valley University to pursue a degree in computer programming. Through his hard work, Cooper's earnings allowed him to pay all of his educational expenses and remain debt-free.

In March 2020, his plans were disrupted by the COVID-19 pandemic. As his father Sean was immunocompromised, Cooper and his siblings moved home to the family's house in Kaysville to spend the duration of the pandemic together.

Some of the best memories of Cooper and Sean were made during this time. Every evening, Cooper's family went for a three-mile walk through the local neighborhoods. Valuable time was spent playing four-square, video games, and watching favorite television shows.

Cooper was instrumental in the family's impromptu six-week RV trip across the country. He learned how to manage the RV's constant maintenance needs and participated significantly in his father's care. The Sullivans visited friends and family in the Northeast states on that trip.

In December 2022, Cooper's father passed due to complications resulting from his own cancer diagnosis. Two months later to the day, Cooper had a sudden brain bleed which required emergency brain surgery. Although the cause proved challenging to diagnose, eventually it was discovered that Cooper had an extremely rare sarcoma in his brain. Treatment throughout his journey included two additional brain surgeries, 40+ sessions of radiation, and countless doses of chemotherapy.

Thanks to the impressive team of doctors and other skilled professionals at the Huntsman Cancer Institute, Cooper was able to live an additional nearly three years of high-quality life.

Cooper loved to attend sporting events and cheer on all of his favorite teams including the Yankees, Patriots, NY Rangers, Celtics, Jazz, Utah Mammoth, and BYU teams. He also was able to travel to countless places with his family during his cancer journey including Key West, New York, San Diego, Denver, Scottsdale, and Hawaii. Each summer, Cooper enjoyed attending many concerts of his favorite artists.

Cooper was talented in his video gaming abilities and quickly learned to play any game-never turning down a challenge. He made countless friends through his favorite game of Destiny 2, all of whom deeply admired his patience and helpfulness. Friends nicknamed him "Sully Goose" in reference to his friendly, jovial nature.

Up until a month before his passing, Cooper found joy in golfing, swimming, and playing pickleball with his family. Everyone who golfed with him was jealous of his once in a lifetime achievement: A hole-in-one. At the age of 10, Cooper made a perfect shot to the absolute shock of his grandfather and brother who were accompanying him.

Cooper blessed all those around him with his quick wit and bright attitude. Everyone in his path commented on how much he shined. These qualities never dimmed throughout his health difficulties. He beautifully followed his father's example of patience and hope through trials. At every turn, Cooper far exceeded expectations for his prognosis and quality of life through his unmatched courage and strength.

Cooper is survived by his mother, Tracie; siblings, Connor and Caroline; brother-in-law, Sonny; and maternal grandmother, Jeanne.

He is preceded in death by his father, Sean Sullivan; paternal grandparents, Paul and Jan Sullivan; and maternal grandfather, William Hefner.

Services in Utah

Cooper's memorial service will be held this Saturday, 11/15, at 11 AM in South Jordan, UT. The family will greet friends and family from 10:00-10:45 AM and lunch will be provided immediately after the service. The address for the church building is 11632 S Night Heron Road, South Jordan, UT.

Services in Connecticut

A memorial service will be held in Cooper's honor on Friday, November 21st, 2025, at 11 am at the Lesko Funeral Home, 1209 Post Road, Fairfield Center. Friends are encouraged to greet the family one hour before the service. For Travel directions or to sign his online guest register, please visit www.LeskoFuneralHome.com.