DENER, Colo. -- DNA evidence has helped solve four Denver area cold case murders from decades ago, and Friday, police revealed the victims were all killed by the same person.
It was the work of investigators using DNA evidence and genealogy that now gives closure to loved ones of those victims.
"She was young, vivacious; she loved children. She was a good student," said George Journey, the brother of one of the victims.
Antoinette Parks had her whole life ahead of her.
Her brothers, George and Karl, think she would have eventually opened up her own daycare.
"If you brought your kid over for her to watch, probably wouldn't get them back," George told KCNC.
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The then 17-year-old never got that chance. She was stabbed to death by a serial killer, according to police.
Denver police said Joe Ervin killed at least four women in the Denver metro area between 1978 and 1981.
Another one of his victims was 33-year-old mother of two, Madeleine Livaudais.
She was a writer and an ecologist who published a book and wrote for magazines.
Her daughters said Ervin robbed them of their mother's light.
"We didn't get to grow up with her and to hear her stories, and to witness the contributions that she could have made to the world," said Livaudais' daughter, Molly.
And those were just two of his victims.
He also allegedly killed Dolores Barajas in 1980 when she was walking to work, as well as Gwendolyn Harris in December of that same year.
His reign of terror came to an end when he was pulled over by Aurora Police Officer Debra Corr in 1981. She was his final victim.
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Officials said he shot Officer Corr with her own gun as she tried to arrest him.
Police eventually tracked him down and Ervin killed himself while in custody soon afterward.
Denver police credit DNA with solving the case.
As early as 2013, officers began linking the cases. Then, through a genealogical DNA search, they identified a possible suspect and then gathered DNA from Ervin's exhumed body.
The families of Parks and Livaudais are grateful.
"It is a great relief to our family to finally have this resolution," said Livaudais' daughter.
"We finally got the closure for you, for us. And, it's just wonderful," Parks' brother added.