The parents of Gus Lamont are urging for help from the public as they desperately seek answers about their missing son, whom they describe as “everything to us.”

On Tuesday, Josh Lamont and Jess Murray renewed their call for assistance in locating Gus, who vanished on September 27 while playing at the Oak Park Station homestead in South Australia’s remote regions, under the watchful eye of his grandmother.

To aid in their search, they shared a recent photograph of their four-year-old son, along with a short 10-second video. The footage captures a barefoot Gus, with his shoulder-length blonde curls, donning a hat and joyfully riding a bike at the station.

“We are united in our grief, and we are united in our search for answers about what happened to our little boy, Gus, who means everything to us,” the parents expressed.

They added, “Our lives have been shattered, and every moment without him is unbearable.”

In their heartfelt appeal, they said, “We know someone out there may have information. If someone knows what happened, we are pleading with that person—or anyone who may have seen or heard anything—to please come forward.”

Even the smallest detail “could give us the answers we so desperately need”, they said.

“All we want is to bring Gus home and understand what happened to our beautiful boy.”

On 5 February, police declared the boy’s disappearance a major crime and said someone living at the remote station was a suspect in his disappearance and likely death.

They confirmed his grandparents, his mother and his younger brother were at the property at the time he disappeared, but emphasised his parents were not suspects.

The disappearance sparked intensive searches spanning almost 500 square km and involving hundreds of police and volunteers, as well as aerial support and mounted units, which have failed to locate Gus or any items belonging to him.

“The tireless efforts of police, emergency services, ADF personnel, volunteers and specialists have meant more to us than we can ever say,” the parents said.

“To the friends, family and supporters who have shown such compassion, concern and assistance during this heartbreaking time: thank you. Your kindness has helped carry us through the darkest days of our lives.”

The boy’s grandparents, Josie and Shannon Murray, released a brief statement via their lawyers earlier in February saying they were “devastated” by the police allegations.

“The family has co-operated fully with the investigation and want nothing more than to find Gus and reunite him with his mum and dad,” they said.

Investigators searched the homestead on 14 and 15 January, seizing items including a vehicle, a motorcycle and electronic devices for forensic testing.

Detective superintendent Darren Fielke earlier in February said family members had been cooperating with police and providing information, which police had reviewed.

On the day the disappearance was declared a major crime, Fielke said police identified “a number of inconsistencies and discrepancies with information as it relates to timelines and the version of events provided to us by the family members”.

“A person who resides at Oak Park Station has withdrawn their support for the police and is no longer cooperating with us,” he said.

Fielke said the investigation had “taken many twists and turns”.

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