For 35 years, the family of Tonya Ethridge McKinley anxiously waited for authorities to track down the man who murdered the gregarious 23-year-old, dumping her body on the side of a Florida highway.

On Wednesday evening, that day finally arrived with the arrest of Daniel Leonard Wells, 57, who was tied to the young woman’s 1985 slaying thanks to DNA recovered from the butt of his cigarette. His arrest marks the beginning of the end of the oldest cold case in Pensacola history.

“She was the best sister a girl could ask for,” her older sister, Renee Ethridge, told The Daily Beast. “God is good. I can’t believe this day has finally arrived.”

Wells was charged Wednesday evening with first-degree murder and first-degree sexual battery for the January 1, 1985, murder of McKinley, according to the Pensacola Police Department. He is currently being held without bond at Escambia County Jail.

McKinley was last seen alive celebrating New Year’s Eve around 1:30 a.m. at Darryl’s Bar & Grille in Pensacola, while her 18-month-old son was waiting for her at home. Four hours later, a family taking their dog to the vet found her body in an empty lot a block from a highway.

The 23-year-old, who was found only partially clothed, had been strangled and sexually assaulted, police said.

Investigators collected physical evidence at the scene and on McKinley’s body—including semen and hair—but they were never able to identify a suspect or make any arrests in the case. They also failed to match DNA found at the scene with samples from a national database.

“Despite having a good bit of physical evidence and dozens of interviews, over time, the trail went cold,” the Pensacola Police Department said in an emotional statement posted on Facebook Thursday. “In the meantime, a baby boy grew up without a mother, parents buried their daughter without knowing justice, and a killer was walking around free.”

Her case went cold, but Pensacola police remained committed to catching McKinley’s killer, and her case was passed around to several detectives over the last 30 years.

“It seems that every couple of years a new lead would pop up and we would drop everything to run it down. We did this time and time again,” the department said in their statement. “When detectives retired, Tonya’s case was passed along to the next generation again and again. As technology advanced, the case was brought back to the forefront. Detectives laid fresh eyes on all of the evidence, new theories were presented, and hopes of catching Tonya’s killer were renewed.”

Over the last couple of years, police have been comparing DNA profiles left behind at old murder scenes with open-source genealogy databases that have become popular among families hoping to find long-lost relatives.

Using a database, Pensacola authorities were able to match DNA evidence found near McKinley’s body with several different people believed to be Wells’ distant cousins. After the hit, authorities constructed a family tree, starting with the distant relatives to determine possible offenders. Eventually, authorities said, the tree led them to identify Wells as a suspect.

The Pensacola Police Department said they followed Wells and were ultimately able to match DNA from a cigarette butt he’d discarded to the evidence they’d collected 35 years ago.

“Today, the evil that took Tonya from her friends and family was arrested for her brutal murder,” the department said. “The reasons why this happened, how evil crossed Tonya’s path, may never be answered and in the end may not be important. What is important is that no one forgot Tonya.”

According to court records obtained by the Pensacola News Journal, Wells has had previous run-ins with Pensacola authorities, including a 1987 arrest for alleged battery and witness tampering. He pleaded no contest to the first charge, and the second was eventually dropped.

A year later, Wells was arrested for alleged solicitation of prostitution, but it’s unclear how the case ended.

Timothy Davidson Jr., McKinley’s 35-year-old son, told The Daily Beast that while he is grateful for the arrest, he will only feel “complete when there is a conviction and justice has been served.”

“It’s still kind of unbelievable—like I’m dreaming,” Davidson Jr. said, adding that his mother “can finally Rest in Peace.”