The mother of allegedly murdered teen Pheobe Bishop has written an open letter in the hope of providing comfort to the parents of missing boy Gus Lamont.

In a post to social media earlier this month, Kylie Johnson urged Lamont’s parents to “keep looking and keeping your hopes alive” after the four-year-old vanished from the grandparents’ remote sheep station near Yunta, South Australia, on September 27.

State police, SES volunteers and Australian Defence Force have spent nearly three weeks searching for Gus with the only clue being a single boot print in the red dirt.

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Johnson spent 22 days waiting for news about her daughter before her remains were found nearby to where she disappeared from in Gin Gin, near Bundaberg, on May 15.

“My advice is that to protect your own mental health and ability to function,” she said in a post to Facebook. “Stay off social media and the news. Keep looking and keeping your hopes alive.”

“Keep your head high. Hold your loved ones closer than ever before and know that you’re not alone.”

She added that she is “an inbox away” for the Lamont family.

“Our porch light will be on for Gus and every other missing person for as long as we live,” Johnson wrote.

“Sending love and healing from our Rural family to yours.”

Pheobe’s roommates, Tanika Bromley, 33, and James Wood, 34, were charged with her murder and interfering with her corpse on June 5, a day before her body was discovered.

Also charged in connection to the case is Kieren Daniel Mittelheuser, who faces two counts of being an accessory after the fact to murder, along with charges including drug possession, fraud and driving while disqualified.

Search efforts for Gus on Thursday were called off as temperatures rose to nearly 40C about midday, but are set to resume on Friday morning.

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