Charlie Stevens: The heartbreaking bittersweet gift left by SA police commissioner's son after he was killed at Schoolies

An organ donor recipient has penned a powerful letter to a top cop and his wife thanking them for a second chance at life after the couple agreed to donate their teenage son's organs.

Charlie Stevens, the son of South Australian Police Commissioner Grant Stevens, was with friends waiting for a bus to head to Schoolies celebrations when he was struck by a car driven by Dhirren Randhawa in Goolwa, south of Adelaide, on November 17 last year.

Charlie, 18, was airlifted to Flinders Medical Centre but died the next day from a severe brain injury, surrounded by his family.

The apprentice tradie's legacy continues after his parents respected his wishes to be an organ donor, which has extended the lives of seven people.

Eight months on, Commissioner Stevens and his wife Emma have already received  letters from three donor recipients and read out parts of one on Channel Seven's Sunrise on Monday. 

'In many ways I've been given the gift of life again, the opportunity to look at the future and see my kids go through school, reach milestone and maybe even get married,' the letter read.

'This is what your family has given me.'

Commissioner Stevens admitted the letters were hard to read but beautiful to  receive.  

'Difficult to read but knowing the impact Charlie has had gives us some sense of comfort,' he said.

Respecting Charlie's wishes was an easy decision for his grieving parents, despite having no idea that he had registered to be a donor on his driver's licence.

'Charlie, he wanted to do that. So we just thought that that would keep Charlie with us for a bit longer, an emotional Ms Stevens said as she fought back tears.

Her husband added: 'We never thought when Charlie did tick that box that we'd be in the situation where our family would be asked to confirm his decision. 

'So it made it so much easier knowing that that's what Charlie wanted.' 

The couple admitted they're still struggling to coming to terms with the tragedy, despite having previously forgiven Rhandhawa.

'We still feel it every day,' Commissioner Stevens said.

'But the way that people in South Australia and right around Australia have reached out to us.

"I suppose it's softened the blow a little bit but it's still very difficult.'

Just 36 per cent of Australians are registered to be an organ donor, a sad reality that Commissioner Stevens and his family wants to see changed.

'We never thought when Charlie did tick that box that we'd be in a situation where our family would be asked to confirm his (organ donation) decision, it made it so much easier knowing that's what Charlie wanted,' he said.

'The more people who sign up, the better offer we will all be. 

'There are 1,800 people waiting for a life-saving donation. The more people who make that decision early in the piece, the more people who are likely to get that gift.'

Rhandhawa was initially charged with causing death by dangerous driving, aggravated driving without due care, leaving the scene of a crash after death and failing to truly answer question.

However, in a plea deal, he admitted to a charge of aggravated driving without due care and leaving the scene of a crash.

Rhandhawa remains free on bail but will reappear in the District Court in August for arraignment and sentencing.

He faces a maximum 12-month prison term and minimum six-month licence disqualification for the careless driving offence.

DonateLife Week begins July 28.