"I will never forget that frantic feeling," she told CBC News in an interview.
Friday will mark 30 years since Christine Jessop was abducted after arriving home alone from school in Queensville, Ont., north of Toronto.
Her body was found on Dec. 31, 1984, in a wooded area in Sunderland, Ont., 56 kilometres from her home. She had been raped and stabbed to death.
"I've been thinking about it. Thirty years is a long time. No doubt about that," Janet Jessop said, when reflecting about her only daughter.
"And I think of who did it. I think of her. What she looked like. What we'd be doing.
"It never goes away and the anniversaries seem to get, I'll say a little bit easier, as time goes on — and yet 30 years. That hits. That hits hard, that you haven't received any answers."
The following year, the Jessops' next-door neighbour, Guy Paul Morin, was charged in Christine’s death. He was acquitted in an initial trial and then wrongfully convicted in a second trial. Advancements in DNA testing eventually cleared him.
An inquiry was held into Morin's wrongful conviction and the original investigation.
The Toronto police took over the case after that inquiry and formed a task force. A complete re-investigation did not lead to an arrest, but the Toronto force has retained the case since then.
The head of the Toronto police cold case squad was a young constable when Christine was murdered. Det.-Sgt. Brian Borg is now a veteran homicide cop who believes the latest DNA technology could provide something police have never had — a description of Christine's killer.
Borg said physical details, such as a suspect’s hair colour, eye colour and ethnicity, can help police focus an investigation.
Janet Jessop is now 72 and lives by herself in a retirement community in Niagara Falls, Ont.
She is far from all the constant reminders of the case and doesn't advertise her tragic past. But she still misses her "always happy, smiling" little girl.
"She would be 39 now. She was nine when she was murdered. That's a lot of time that we could've spent together and enjoyed each other. So, yes. It's an important year. A very important year."
Christine's big brother Ken Jessop also lives far away from the memories in Crystal Beach, Ont., with his wife, Tracey.
He, too, needs answers and tries to find them through a Facebook page he set up called Justice for Christine.
"I think we're down to the science, finding our answers now," he said.
Christine Jessop is buried in the Queensville cemetery where she used to play behind her home. This milestone anniversary is particularly important to her mother, who fears it might be the last chance for publicity.
Janet Jessop doesn't care if the killer is alive or dead.
She just wants to know who it is.
"It would mean really an end. A complete and total end. We have Christine back, that's fine, but it's still unfinished," she said.
And while new science is promising, cold case investigators need tips to narrow the field of suspects.
So once again, Christine's family is appealing for help.
"I think it's important to keep her memory alive," said Ken Jessop. "As alive as it is for my mother and I... because you never know."
Anyone with information on the abduction and killing of Christine Jessop is urged to call the homicide squad at 416-808-7400 or Crime Stoppers.
CBC viewers can watch Sue Sgambati's full report on CBC Toronto at 5 p.m. on Thursday.
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