Audrey Moran, whose son Zackary Sullivan was killed in a shooting two weeks ago, was overwhelmed with gratitude by the vigil in his memory Friday night.

“Zackary was my best friend — and my son. And January 16 is a nightmare that I’m never going to wake up from,” Moran said, looking out at a crowd of mostly young people, their faces glowing orange over candlelight and their arms interlocked and around one another. “We couldn’t do this and continue forward without everybody’s help.”

Change for Concord, an advocacy group that works to empower younger generations and improve their lives in the city, hosted a vigil to honor Sullivan’s life in Eagle Square Friday night, with about 75 people in attendance.

Sullivan, a Concord resident and 2022 graduate of CSI Charter School in Penacook, was “constantly tinkering with all things mechanical,” according to his obituary . Eager to dive into the workforce and a devout auto enthusiast, he started a mobile car detailing business last summer, which he then expanded to a brick-and-mortar location. It opened on January 1, just two weeks before his death.

Sullivan was living proof “that young people can own businesses, can have opportunities, can grow and can become the people they want to become,” said Fisto Ndayishimiye, lead organizer with Change for Concord, in opening remarks Friday. “And yet we are here, crying that he’s gone.”

After graduating from high school a year early, Sullivan was eager to get out into the workforce.

“I’ve never met a kid his age that was as mature as him and just had the work ethic and passion that he did. He’s still inspires me to this day to work harder and be a better person,” said Kody Wheeler, 19. “He was my best friend.”

Beyond that drive, his loved ones said, Sullivan was caring and generous.

“Anyone who had the honor of knowing Zackary knows how much his family and friends meant to him,” his obituary said. “There was never any question – if you needed something, Zackary was the one to call.”

Moran remembered her son as reliable, someone she could call to give her hand or lighten her load.

She described a trip to the store they took together over the summer. Driving separately, his car ended up just ahead of hers at a toll booth.

“The toll worker said, ‘the person in front of you paid your way,’ ” Moran recalled. “I like to think he would still be paying my way to this day.”

With their investigation ongoing, the state Department of Justice and Concord Police have released few details about Sullivan’s death, other than to say he died from a gunshot wound to the neck.

Police were called to the Dunkin Donuts at the intersection of Manchester Street and Garvins Falls Road on the night of January 16, and the road was closed for hours as they investigated what happened.

It is important to remember Sullivan’s lead-by-example inspiration to young people in Concord, Ndayishimiye said. He also deserves justice.

“We must advocate to make sure that our communities are safe and our young people are safe,” he said. “They’re the future of our country and the future of our community.”

Attendees in the crowd, some who knew Sullivan well and others who said they were close to his large family, were awestruck at the suddenness of the loss.

“What happened to him was the furthest thing from my mind ever happening to such a normal, intelligent, funny person,” said Marian Scott, a friend of the family who said she also had been a customer of Sullivan’s blossoming business.

“I can’t believe it’s real. As much as I want to, I can’t,” Wheeler said. “You don’t realize how small the world is, and how fast things can change.”