Like a number of Aussie kids in the early '90s, 12-year-old Rhianna Barreau had an overseas penpal.
She had built up quite a bond with her American correspondent, and wanted to buy her a Christmas card.
It was only October, but this was 1992, and international post was slower in those days. Her mother Paula had to work that day, but Rhianna was on school holidays, and so the pair arranged for Rhianna to walk to a nearby newsagency to buy the card. There was a bus strike that day, so walking was her only option, reports news.com.au.
Rhianna's mother left the house at 8:30am that morning.
It was the last time she would see her daughter alive.
In the 26 years that have passed, Rhianna's whereabouts have remained unknown, despite extensive search efforts and public pleas.
Rhianna Barreau lived in Morphett Vale, South Australia.
Her home, on Wakefield Avenue, was roughly 250 metres from the Southern Expressway, which cut through the suburb, parallel to her street.
Morphett Vale is a busy suburb, but a suburb all the same, so Rhianna's mother wasn't too concerned about her walking alone to the nearby shopping centre.
Throughout that day, Rhianna's movements were clocked by a number of individuals. According to eye witness reports, she was seen leaving her home at 10:30am, presumably to walk to the newsagency.
Records show that she bought the card at 11:19am at the Reynella Shopping Centre, and was later spotted cutting through both Morphett Vale High School and Stanvac Primary School during a half-hour window shortly after noon.
In both instances, she was seen carrying a small bag, which detectives assumed contained the Christmas card for her penpal.
Her mother arrived home from work at 4:10pm to a normal scene: a locked door, the television blasting afternoon programming, a record sitting on the living room floor as if it had been played and then carelessly discarded.
Most tellingly, the Christmas card Rhianna had been so eager to buy was sitting on the table, meaning that she had returned home at some point in the afternoon.
Only Rhianna was nowhere to be seen.
None of her personal belongings were missing.
If she had left of her own accord, she didn't expect to be gone for long.
Police surmised that it was more likely that she didn't.
Panicked, Paula Barreau called her daughter's friends, knocked on neighbours door, and by 6pm was panicked enough to file a missing person's report.
"I was hoping she was just at a friend's place and had forgotten what the time was — but that's not like her," Paula Barreau told Adelaide Now in 2015, the first time she had spoken publicly about her daughter's disappearance since the abduction, and the only interview either parent has conducted to date.
More details of Rhianna's movements that day emerged.
Just ten minutes before her mother returned home, Rhianna was spotted near a junction roughly 500 metres from her house.
She was alone, but — according to her official Missing Persons report — "Suspicious activities occurred at Acre Avenue, David Terrace, Highwray Avenue, and Crittenden Avenue Morphett Vale."
Just what these suspicious activities were has never been revealed by the police, but they all involved a white Holden Torana with Victorian registration plates.
Despite a widespread search, neither this vehicle nor its owner was ever located.
A one million dollar reward for information and thousands of hours of investigations have turned over nothing substantial in the past 26 years.
Paula accepts her daughter is most likely dead, although she spent years refusing to move house in the vein hope that Rhianna may one day return.
She has since moved — "it got to the stage I just couldn't stand living there and had to move away" — but still holds out hope for some form of closure.
"It is the just not knowing, because it is just ongoing", she said in 2015.
"I don't know if it's ever going to come about in my lifetime, that's what I am scared of."
Her theory is that Rhianna knew her killer, claiming her daughter would have screamed "blue murder" had the abduction been at the hands of a stranger.
"I would assume if she was on the street there would have been someone in the vicinity who would have heard that. My feeling is it was somebody she knew. That's what I can't understand."
Last August, as part of National Missing Persons Week, the South Australian Police again highlighted Rhianna's case, which was 25 years old at that point.
This time around, anyone with information was offered not just the million-dollar reward, but immunity.
Major Crime Detective Superintendent Des Bray is hopeful these twin incentives will help with provide the family with closure.
"It is time for those with information to come forward and do the right thing," he said.
"More importantly, information provided may enable us to find Rhianna and return her to her family, and make the person responsible pay for the terrible crime they have committed.
"Do not let those responsible continue to walk free among us."