There is a grey, liminal space where loved ones of missing people often find themselves in the aftermath of disappearance.
Social workers describe it as a feeling of ambiguous loss.
Missing persons researcher Professor Sarah Wayland knows the space well.
Professor Wayland sought permission from the family member before being interviewed by the ABC.
The four-year-old was reportedly last seen playing in sand at his family's remote, outback South Australian sheep station one year ago today.
Until earlier this week, Gus's parents, Jess and Josh, avoided public attention.
"We believe that someone knows something," Josh said, leaning forward with his hands clasped, staring down the barrel of the camera.
Suzie Ratcliffe has replayed the video of Josh and Jess several times.
Fourteen months before Ms Ratcliffe was born, her 11-year-old sister, Joanne, along with four-year-old Kirste Gordon, went missing during a football game at Adelaide Oval in 1973.
Along with the disappearance of Gus and the Beaumont children, their suspected abduction remains one of South Australia's unsolved missing children's cases.
Ms Ratcliffe is today the director of missing persons awareness organisation Leave a Light On.
The small town of Yunta is now indelibly linked to the boy's disappearance.
Yunta local Keith Noble says Gus's disappearance is "on everybody's mind", and finding him would "mean a lot" to the community.
Professor Wayland believes there are two reasons why, of the almost 50,000 missing persons reports filed in Australia last year, Gus's disappearance has preceded so much attention.
With Gus's name once again making national and international headlines on the first anniversary of his disappearance, Professor Wayland has urged kindness.