On Tuesday, March 18, 1986, Sharon Fulton had plans to attend a friend's party.

She never made it.

The last time she was seen, she was dropping one of her young children off in Wangara, a suburb in Perth's north.

Three days later, her husband Raymond Reddington, known at the time as Robert Fulton, reported his wife missing to police, telling various stories, including that he had dropped her off at a train station and that she was seeing another man.

At one point, per the ABC, he suggested that she was a victim of the serial killers David and Catherine Birnie.

Now, 40 years later, Reddington has been sentenced to life in prison for her murder.

Last month, a WA Supreme Court jury found the 79-year-old guilty of murdering Sharon at the family's Perth home in March 1986.

Sharon was 39 years old at the time of her murder. She had four young children.

Her body has never been found.

On Monday, Reddington was sentenced to life imprisonment, eligible for parole after serving 20 years, if he reveals where his wife's body is.

"The deceased should have been safe in your company," Justice Joseph McGrath said as he handed down the sentence.

"Instead, you killed the deceased in an act of violence.

"You have caused immense grief."

Sharon had started divorce proceedings in the year before her death, Justice McGrath said.

"Your marriage had challenges, and you were having affairs ... the deceased was aware of your infidelity," he said.

Reddington, a former RAAF officer, was concerned about losing access to his children and the looming financial hit he would take if the couple split.

"You had a motive to kill," McGrath said.

On the morning of March 18, the day Sharon went missing, Reddington told his boss he had a "domestic issue" before leaving work at RAAF base Pearce and driving home.

"Shortly after you arrived at home, you killed the deceased," McGrath said.

"It is not known when you disposed of the deceased's body or how you did it.

"It has meant your children have not known what happened to their mother."

In the months before Reddington murdered Sharon, he had taken out two $120,000 life insurance policies for his wife and himself, which was "a significant sum in 1986," McGrath said.

Outside the court, his youngest son, Heath Fulton, who was three years old in 1986, said the sentence was half the time his father had spent enjoying his life after murdering his mother.

Finding Sharon's remains was his and his siblings' main focus, he said.

"It's the ultimate, and it's the only thing we pretty much live for — to bring her home," he said.

Reddington's sentence was backdated to October 25, 2023, when he was taken into custody and extradited from NSW to WA.

The court heard he's unlikely to see freedom again, as he is battling cancer and a slew of other health issues and could have as little as 18 months to live.

Reddington, who was 39 years old when he killed his wife, continues to claim he is innocent.

"His conviction for the crime of wilful murder will continue to trouble the conscience of our community," his lawyer, Jonathan Davies, said outside court.

— with AAP.

Feature image: Facebook/Australian Missing Persons Register.

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