The case has been referred to the Coroners Court of Victoria, which has confirmed the investigation remains active.

Police confirmed they were preparing a report for the coroner in 2016. The report had yet to be lodged in June 2017.

Krystal was 23 years old and heavily pregnant when she was last seen in Pyramid Hill on June 20, 2009.

She was due to give birth to her first child, a baby boy she had intended to name Ryan, within days of her disappearance.

The identity of the baby's father is not known.

One of Krystal's last known movements was checking herself out of Bendigo Health's maternity accommodation the day she vanished.

She was believed to have been taken to the hospital by ambulance days earlier, due to labour pains.

Krystal had planned to give birth at the hospital.

She caught a train from Bendigo back to Pyramid Hill the day she disappeared, arriving about 8.30pm.

Krystal was familiar with the route, having been a frequent train user who regularly stopped at stations between Bendigo and Swan Hill. She did not drive.

She was seen leaving a friend's house at Albert Street, Pyramid Hill, about 9.40pm.

Krystal was believed to have been headed back to her unit.

A telephone call was placed to Krystal's mobile phone from a public telephone outside a post office at Leitchville, more than 30 kilometres from Pyramid Hill, just before midnight.

The caller was believed to have been the last person to speak to Krystal before she vanished.

Krystal's phone was tracked travelling towards Leitchville about 3am.

Police suspected Krystal was killed because she had not used her mobile phone, touched her bank account or visited a hospital since she was last seen.

Police in 2012 said Krystal's disappearance was also "completely out of character".

"She would talk two or three times a day to her family via text or phone," the lead investigator at the time, Detective Sergeant Wayne Woltsche, said.

"And she didn't have any means or mechanisms to just disappear."

Krystal's remains were never recovered.

Homicide squad detectives and as many as 40 volunteers searched a property about 10 kilometres east of Pyramid Hill in October, 2009, after receiving two tip-offs about the likely location of Krystal's body.

She was last seen wearing an orange top, black tracksuit pants and a camouflage-patterned baseball cap.

A flyer posted on the windows of several businesses in Pyramid Hill in 2009 stated Krystal often wore a baseball cap.

It said she had a deep voice and was streetwise, very friendly and trusting. The same flyer stated Krystal had epilepsy and asthma.

Krystal also lived with a mild, undiagonsed intellectual disability - the result of bleeding on her brain at birth.

Krystal was well known in the Pyramid Hill community.

She was described as 167 centimetres tall, with short brown hair and crooked teeth.

Police in 2009 believed Krystal had been to a hairdresser in Pyramid Hill the day before she went missing.

Krystal was known to have spent a large proportion of her time browsing the internet and rarely strayed far from her phone.

Police in 2009 believed Krystal used the name Kylie Wright in internet chat rooms.

The fact she did not access the internet after her disappearance was believed to be the first sign something was wrong.

The arrest of a 61-year-old Pyramid Hill man at Pyramid Hill last year brought hopes of a breakthrough in the case. But the man was interviewed by police and released pending further inquiries.

Police confirmed within months the man was no longer considered to be a person of interest in the case.

A reward of up to $100,000 was announced in June 2012 for information leading to the apprehension and subsequent conviction of the person or persons responsible for Krystal's death.

The reward was to be paid at the Chief Commissioner's discretion.

The Department of Public Prosecutions said it would also consider granting indemnification from prosecution to any person who provided information about the identity of Krystal's killer or killers.

Police yesterday said investigators were still keen to speak with anyone with information about Krystal's disappearance.

Krystal's mother, Karen Fraser, told the Bendigo Advertiser in 2016 she yearned for closure.

"It would be nice to have the answers, to be able to have the body back to lay to rest," she said.

She believed all the evidence pointed to foul play.

"The only way out of Pyramid Hill at that time of night, after the last train has left, is by car or on foot. There's no way she could've walked, she was that pregnant," Mrs Fraser said.

"She couldn't have walked to Cohuna, Kerang or Bendigo, or anywhere else. Someone had to have driven her."

Mrs Fraser told the Bendigo Advertiser somebody out there knew something.

"We all just want answers," she said.

She said five years after Krystal vanished she knew no more than than when her daughter first disappeared.

Police yesterday urged anyone with information to contact Crime Stoppers on 1800 333 000 or to submit a confidential report at www.crimestoppersvic.com.au

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