PITTSBURGH (KDKA) — The disappearance and murder of 15-year-old Christine Guenther has been a local cold case since 1981; but as the 30th anniversary of her death approaches, family and friends say they are more determined than ever to help investigators solve the mystery.

Family and friends gathered at Guenther’s gravesite today to share memories and seek justice in the 15-year-old’s death.

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In 1981, Guenther disappeared while waiting at a bus stop in Peters Township.

“Since the loss of you, I’ve learned how to hold the tears when I want to cry because all I have is memories and just want to ask God why,” said Christine Wallace, a childhood friend of Guenther’s, during the memorial service.

A few days after her disappearance, Guenther’s body was found in Allegheny County.

For the last 30 years her murder has remained unsolved, but her friends recently started a Facebook page.

“We’ve been using social media and the Internet to spread the word of her case still being unsolved, and what happened and where she was and where she was found,” said Wallace.

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Guenther’s mother now lives in Florida, but she’s touched deeply by local efforts to keep the case alive.

“You always know the special qualities that your children have, and Chris had the quality of being friends with everyone,” said Carmen Guenther Mader, the victim’s mother.

The events may have happened 30 years ago, but Guenther’s family and friends say they will never let it be forgotten.

“I don’t think it’s a matter of if, I think it’s just a matter of when,” said Nicole Mayor, Guenther’s cousin. “I think there’s people out there that have bits and pieces of it.”

“We’re old enough where we feel we can do something about and keep her case in the public eye,” Wallace added.

On Monday, the same group will gather under a billboard on Route 19. It will activated Oct. 31 , the same date and at the same time Guenther’s body was found 30 years ago.

It will include details about the case in the hopes that someone will come forward with information that can help police.

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Facebook: Justice for Christine Guenther
Group Launches Facebook Page In Hopes Of Solving 30-Year-Old Murder