When the family of a 16-year-old missing from St. Paul for 40 years gathered on Monday with an Illinois police investigator, he confirmed their nightmare.

“I regret to inform you that your brother, Jimmy, is victim No. 24 of John Gacy,” he told them.

The identification of James Haakenson after all these years brought mixed emotions for Haakenson’s older sister, Lorie Sisterman.

“We know where my brother is,” Sisterman said on Wednesday. “We know what happened to him.”

And while the family wanted those answers, they’re now aware of the horror of his fate.

“This man was a horrible monster, and my brother somehow ran into him,” Sisterman said of Gacy. “Somehow, on the bus or on a street corner, just being in the wrong place at the wrong time.”

From the time police arrested notorious serial killer Gacy in Chicago in 1978, Haakenson’s relatives wondered whether Gacy could have preyed on him. Haakenson’s mother asked police to look into a connection, but no dental records were available — the only means to make an identification then.

As the years passed, one of Haakenson’s nephews — a young man who never met his uncle — would not give up on bringing closure to his family. He conducted research of his own and contacted the Cook County, Illinois, sheriff’s office.

Ultimately, with DNA samples from one of Haakenson’s brother and his sister, authorities were able to identify James Haakenson as one of Gacy’s 33 victims. Related Articles St. Paul PD highlights surveillance photos of looting suspects, seeks tips

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Sisterman said that the moment it became real for her Monday was when investigators showed her photographs of Haakenson’s grave. The headstone has no name and says, “We Remembered.” Funeral homes in the Chicago area paid for caskets, burial and headstones for Gacy’s eight unidentified victims.

JIMMY WAS ‘A FUN-LOVING KID’

Jimmy Haakenson was living with his family on York Avenue, near Arcade Street in St. Paul’s Payne-Phalen neighborhood, when he left home, saying, “I’m going to Chicago.”

Haakenson was “a fun-loving kid, but he also was a little troubled,” said Sisterman, of North St. Paul.

She said their father was an alcoholic who would come and go, and she felt Jimmy really needed his dad in his life.

Meanwhile, their mother had to put food on the table for her four children. She worked at a factory by day, a sandwich shop at night and cleaned hotel rooms on the weekends. Sisterman, the oldest of the kids and the only girl, became the “mom” when her mother was at work.

In many ways, Jimmy was “just a typical little boy,” his sister said. Photographs show him on a bicycle and using a microphone to record his singing — “he was kind of a ham,” Sisterman said with a smile.

Sometime after he turned 16 in June 1976, Jimmy left home. His family doesn’t know how he made his way to Chicago.

CALL TO MOM, THEN NEVER HEARD FROM AGAIN

On Aug. 5, 1976, Jimmy Haakenson called his mother and told her he was in Chicago. Sisterman imagines he said things like, “I’m safe. I’m here, Mom. Don’t worry.”

Haakenson was never heard from again, and Sisterman said her mother went to Chicago looking for him.

Cook County Sheriff Tom Dart said during a Wednesday press conference that Gacy likely killed the teen within hours of the call, adding that he would not be surprised if Haakenson phoned his mother from Gacy’s house.

It’s unknown how Gacy found Haakenson. Most of the cases involved Gacy luring young men with the promise of a job, cruising areas where gay men hung out, or targeting young men who were alone, Dart said.

Gacy mostly buried his victims in the crawl space under his house. Because he killed so many, he ended up putting their bodies on top of each other, Dart said. Haakenson was next to a young man who was identified when his body was found — Rick Johnston, whose date of last contact was Aug. 6, 1976, one day after Haakenson was heard from. That information helped investigators narrow the time frame that Haakenson was likely murdered.

Soon after Gacy was arrested in December 1978, Haakenson’s mother was concerned that her son could have been one of his victims. A St. Paul police missing-persons investigator wrote to police in Illinois in January 1979.

“They definitely were a very concerned family,” Dart said. “This was beyond horrific and they were very engaged, but at that point in time … there wasn’t even a notion that DNA was on the horizon. It was just, ‘If you don’t have dental records, there’s nothing we can do.’ ”

Gacy was a contractor in Chicago’s northwest suburbs in the 1970s. He also worked as an amateur children’s clown.

Gacy lured victims to his car, rendered them unconscious with chloroform and sometimes tortured them at his house before killing them. It took authorities months to retrieve bodies and evidence from under the crawl space of his house and yard.

Gacy was found guilty in 1980 of 33 murders. He was executed at the Stateville Correctional Center in Joliet in 1994.

RELATED: Timeline of John Wayne Gacy’s case

Wednesday’s news makes Haakenson the second Minnesota victim of Gacy.

University of Minnesota architecture student Russell Nelson, 22, of Cloquet, was kidnapped outside a bar in Chicago in October 1977. His remains were later identified with others in the infamous crawl space in Gacy’s home, according to reports in the St. Paul Dispatch.

NEPHEW PUSHED FOR ANSWERS

In 2011, the Cook County sheriff reopened the investigation to identify the eight remaining Gacy victims who were unnamed. Two have since been identified — William Bundy and now Haakenson. The investigation into the remaining six unidentified victims continues.

RELATED: Another of John Wayne Gacy’s victims: a 22-year-old UMN student

Haakenson’s nephew contacted the Cook County sheriff’s office after he discovered their work to connect unidentified victims of Gacy through DNA of surviving family members.

“He became obsessed: ‘What happened to Jimmy?’ ” Sisterman said of her nephew. “He’s the person who started everything to get this solved, and he pursued it and he pursued it.”

The case also shows the lengths that investigators go to get answers for families, said St. Paul Police Cmdr. Kevin Casper, who heads the unit that handles missing-persons cases. When Cook County investigators came to St. Paul police headquarters Monday to inform Casper of the connection between Haakenson and Gacy, Casper said the revelation hit him “like a ton of bricks.”

Casper encourages families of missing people in Minnesota to provide DNA samples to the Minnesota Bureau of Criminal Apprehension. The state agency recently dug up remains of five unidentified bodies from several east-metro graveyards and tested them against national DNA databases but found not a single match. The BCA held three DNA-collection events for families of missing people this month and the final one is scheduled for 4:30-6:30 p.m. July 27 at the Blue Earth County Justice Center in Mankato.

For Sisterman, she has been in a fog since the investigator informed her of the DNA results in her brother’s case.

She used to try to imagine her little brother in Tahiti, sipping a drink.

But she would ask herself why he had not contacted them. Then, she would wonder, “Is he lonely? Did he die?”

The family plans to have Haakenson’s name added to his headstone, plus the dates of his life, said Sisterman, 61. The date on it now is when he was buried. Related Articles St. Paul PD highlights surveillance photos of looting suspects, seeks tips

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She said she was overcome by emotion to hear that people who never met Haakenson cared enough to give him a proper burial.

Haakenson’s parents never learned what happened to their son: Jimmy’s father died in 1977 and his mother in 2008.

“I’m glad my mom is already gone, so she didn’t find out the awful things that happened to her son, but then she went to her grave not knowing where her son was,” Sisterman said.

Dave Orrick contributed to this report.