Matthew Leveson’s parents promised to find their son and give him a proper farewell and, after more than a decade searching for answers, they’re about to do just that.

“It’s our final goodbye,” Mark Leveson told AAP ahead of Friday’s funeral for his 20-year-old son whose body was found in the Royal National Park in mid-2017.

“It’s the culmination of 10-and-a-half years of work.”

Mark and Faye’s emotional and exhausting journey has been fraught with suspicion, frustration, disbelief and determination.

Much of the fight took place in the public spotlight as the man they believe murdered Matt – his former partner Michael Atkins – broke new legal ground.

Matt was last seen leaving Darlinghurst’s ARQ nightclub with Atkins in September 2007.

Suspicion fell on the then-44-year-old Atkins, who was subsequently seen on CCTV footage buying a garden mattock and gaffer tape from a hardware shop the same day.

He was arrested in 2008 and charged with murder but ultimately acquitted by a NSW Supreme Court jury in 2009.

Years of uncertainty followed. A reward of $100,000 was offered and later increased to $250,000. Atkins continued to deny involvement as Matt’s parents pleaded for information.

The case broke new legal ground when Atkins was granted immunity from contempt and perjury charges over evidence he gave at Matt’s inquest on the condition he led police to the body.

For the Levesons, desperate to find their son’s remains and give him the dignified burial he deserved, it was a deal with the devil.

Police searched bushland near the town of Waterfall, south of Sydney, for six months based on the information provided by Atkins.

Digging machinery ground to a halt in late May 2017 when a skeleton was uncovered beneath a cabbage-tree palm in the national park.

Mark and Faye embraced. They had found their son.

The coronial inquest in 2017 heard Atkins told police he found Mr Leveson’s body in their bedroom after their night out and assumed he had overdosed.

Atkins said he was worried about his reputation so decided to bury Matt’s body in the park.

Deputy state coroner Elaine Truscott wasn’t able to rule on a cause of death but said the lies Atkins told gave rise to “a considerable degree of suspicion”.

The very mention of Atkins’ name disgusts Faye Leveson. She refers to him as “it”.

The Levesons relocated the palm under which Matt was found to their backyard.

As they prepare to say their final goodbye, they’re insisting the Sydney service doesn’t reference the court cases, inquests or searches.

Instead, they’ll share with guests who Matt really was: a bright, vibrant, creative, caring son whose company they enjoyed for 20 years.

“He was just a lovely kid and we want people to see that side of him, not what’s been put in the papers,” his mother says.

“This is a celebration of his life.”

-AAP