Sonya found a paedophile in her daughter's bed, weeks before her death.

It’s every parent’s worst nightmare.

In January 2009 Carly Ryan’s mum, Sonya, found a paedophile in her teenage daughter’s bed. Just a few weeks later, 15-year-old Carly was dead.

Now Ryan has spoken about the night she came across that harrowing scene.

“I walked past Carly’s bedroom and he was lying on her bed on top of the covers and I immediately went … ‘Oh God, why is he in there?’,” she told Sunday Night.

“I just woke them up and said to him, ‘You need to get out of my house. You need to get your things, you need to get out’.”

The man in Carly’s bed was 50-year-old Garry Francis Newman. Carly met Newman online while he was pretending to be an 18-year-old musician from Melbourne named ‘Brandon Kane’. She was just 14 years old at the time.

Over several months Carly chatted intensely with Newman as he slowly groomed her from his Melbourne home.

He then flew from Melbourne to Adelaide to visit Carly and her mum under the guise of being Brandon Kane's father 'Shane'.

Newman told the young girl and her mother he was dropping off some birthday presents for her. When he told them he didn't have a hotel room booked, Sonya invited him to stay the night.

Later that night she found Newman in Carly's bed. She immediately kicked him out of the house.

But several weeks later, unbeknownst to Sonya, Newman travelled back to Melbourne and lured 15-year-old Carly to a remote beach.

Carly thought she was finally going to meet 18-year-old Brandon, but when she arrived at the beach she was greeted by Newman.

In an act of revenge, Newman bashed the Adelaide schoolgirl until she was unconscious, pushed her face into the sand to suffocate her, and then threw her into the water to drown.

In 2010 he was jailed for life for the crime.

Trish Kelly, the South Australian Supreme Court judge who presided over the trial in 2010, said Newman was a "predator" with a "grossly perverted plan to deceive, seduce and murder Carly" because he couldn't get his own way.

Kelly said Carly had fallen in love "with the idea of the handsome, musically inclined and rather exotic Brandon Kane" when the "real man was in fact an overweight, balding, middle-aged paedophile with sex and murder on his mind".

On Sunday Night Sonya recalled the last time she saw her daughter alive.

"It wasn't until she was at the door that she kind of looked at me in a funny way and I thought, 'Give me a hug'," she said.

"So I gave her a big hug and then she wanted another one and then she wanted another one and then by the end of it we had four hugs at the door and then she goes, 'Love you, Mum,' and just skipped off the verandah."

After her daughter's tragic death, Sonya Ryan set up the Carly Ryan Foundation to educate children and parents about online safety. In 2013, Sonya was named the South Australian of the Year for her work with the foundation.

In March 2017, after a decade of tireless campaigning, the Federal Government introduced 'Carly's Law' to "target online predators preparing or planning to cause harm to, procure, or engage in sexual activity with a child”.

Under the law, authorities will be able to prosecute those lying about their age to minors online and intervene before a predator can act. It will also target those who misrepresent their age, with offenders facing 10 years imprisonment.

You can find out more about the Carly Ryan Foundation and Carly's Law here.

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