Cold Case Files: Ontario police continue to hunt Yvonne Leroux’s killer 44 years later

Diane Leroux has seen a lifetime pass and still has no answers around who killed her 16-year-old daughter, Yvonne Leroux.

“You think about it over the years, she was only 16. I have grandchildren from my oldest daughter, from my son and my youngest daughter. I have none from her,” Diane said.

“She never grew up. She never got married. She never had a chance in life. It’s just something you cannot describe.”

Tweet This Click to share quote on Twitter: "She never grew up. She never got married. She never had a chance in life. It's just something you cannot describe."

Police said the Ontario-area teenager was living a “high risk lifestyle when she went missing in November 1972.”

READ MORE: 32 years later, Ontario mother still searching for daughter’s killer

“Yvonne would hitchhike to wherever she wanted to go. She didn’t have any issues with accepting rides from strangers,” Sposato said. “She was travelling from Toronto to Windsor frequently.”

Yvonne would often misrepresent her age and go by the names JJ and Linda Jessop.

In 1971, Diane said Yvonne was the victim of an assault and became a different person.

“Her self-esteem was down to zero and she just felt like she wasn’t worth anything,” Diane said.

Tweet This Click to share quote on Twitter: "Her self-esteem was down to zero and she just felt like she wasn't worth anything," Diane said.

That’s when she said Yvonne made an attempt to turn her life around.

WATCH: Extended interviews with Yvonne Leroux’s mother, Diane Leroux. 

1:47 WATCH: Extended interviews with Yvonne Leroux’s mother, Diane Leroux.

On Nov. 30, 1972, Yvonne was attending a teen counselling group at a clinic by York Finch Hospital.

She was last seen leaving the group at approximately 10 p.m. that evening.

Sposato said Yvonne’s body was found hours later in King Township.

“Yvonne was found by people that live in the area and they contacted York Regional Police,” Sposato said.

“Police attended and investigated and it was deemed that she was killed and it was a homicide.”

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The coroner determined the cause of death was blunt force trauma to the head.

“Something that you had is gone and it’s gone and gone forever,” said Diane. “And there’s nothing you can do about it.”

It’s been 44 years since Yvonne’s death and police are still on the hunt for the person responsible.

“Currently there is a $50,000 dollar reward for anyone who can provide any help that would lead to the arrest of the individual who was responsible for Yvonne’s death,” Sposato said.

And Diane is still searching for answers.

“Nothing is ever going to bring things back to where they were or bring her back. But I would like to have justice.”

Tweet This Click to share quote on Twitter: "Nothing is ever going to bring things back to where they were or bring her back. But I would like to have justice."

Police are urging anyone with information on Yvonne’s death to contact York Regional Police Cold Case Unit at 1-866-876-5423 ext. 7865 or report a tip anonymously to Crime Stoppers at 1-800-222-8477.

Watch Global News at 5:30 & 6 p.m. ET Thursdays for our weekly Cold Case Files series.

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