For 35 years, Teri Stack lived with the "agonizing thought" her sister's killer would never be brought to justice.
On Thursday, she put that notion to rest.
Stack was in a DuPage County courtroom as Michael Whitney, 58, admitted fatally stabbing her 28-year-old sister Darlene in a Wheaton boardinghouse in August 1976.
"Now we can all have a bit of closure, but we will never forget the loss of Darlene," Stack wrote in a statement. "She was so full of life and had overcome so much to have her life end so senselessly."
Whitney displayed no outward emotion as he entered a guilty plea in exchange for a life sentence without the possibility of parole.
Judge Kathryn Creswell questioned him for several minutes about whether he understood the penalty.
"By natural life, I mean you will die in prison. You'll never be released. Do you understand that?" the judge asked.
"Yes," Whitney replied.
Whitney, who was charged in Darlene Stack's murder just last month, had been due to be paroled next year from a 60-year term for an unrelated 1982 murder in Carol Stream. But he told a judge at his first court appearance he intended to plead guilty.
"It's his case and he's been very consistent," Assistant Public Defender Mike Mara, who represented Whitney, said. "There was never any wavering. He wanted to plead guilty. We didn't talk about why. He just wanted to do it."
Whitney had the option of defending the case under 1976 sentencing laws, which called for a minimum term of 14 years. Instead, he opted for life, which would be mandatory under today's laws because he has been convicted of two murders.
State's Attorney Robert Berlin said he hoped Whitney's admission would bring peace to those affected by the "vicious" killing of Stack.
"It is my sincerest hope that while their pain may still linger, the family and friends of Darlene Stack may be able to finally close this horrible chapter in their lives," he said.
Whitney, who told the judge he dropped out of high school and could read and write only "a little," was charged with Stack's murder after semen collected from the crime scene was matched to his DNA.
His former girlfriend subsequently confessed she provided a false alibi for him.
Assistant State's Attorney Joe Ruggiero said Stack was raped and stabbed 33 times in the upstairs of a boardinghouse on North Stoddard Avenue in Wheaton, where she and Whitney both rented rooms in August 1976.
In the hours following the killing, prosecutors said, Whitney admitted he'd murdered Stack to his girlfriend, who told investigators she saw him later throw a bloody knife into DuPage River in Winfield. Had the case proceeded to trial, Ruggiero said, Stack's former landlord also would have testified that on the night of the murder she saw Whitney's girlfriend watching TV in their basement apartment alone and later saw the couple leave in a car with Whitney carrying a bag.
Hours later, after Stack failed to respond to several knocks on her door, police busted in and found her body.
"She was stripped, bloody, stabbed several times. Her hands were tied behind her back with bed sheets and her mouth was gagged," Ruggiero said in court Thursday.
Although authorities long considered Whitney a suspect, the case remained uncharged until Wheaton police reopened their investigation in 2005. They later matched evidence from the crime scene to Whitney's DNA, which was on file in a law enforcement database of felons by then.
Teri Stack said her sister was one of four siblings raised as orphans. Despite that fact, she said, Darlene "believed in a future and was enthusiastic about furthering her education."
She said Darlene moved into the boardinghouse less than a week before her murder to be close to Central DuPage Hospital, where she was interning as a medical technician student. Her sister said she also was engaged to be married.
"For years and years we lived with the agonizing thought that Darlene's death would not be avenged," she said. "Now we can have closure, but the pain will always linger."