Patrick Harris was in high school when he found out his girlfriend's mother had lost her battle with skin cancer.
The 18-year-old lifeguard, of Sorrento, said the impact the death had on the family made him realise how easily the preventable cancer could strike down a loved one.
While most high school graduates waiting to hear if they have been accepted into university are enjoying the summer break, Patrick has been training tirelessly for a 27.5km solo paddle from Rottnest Island to Sorrento beach. He will be the only paddler to attempt the Fenn Nelo Doctor, one of Australia's biggest ocean paddling events, on a surf lifesaving paddle board at the weekend, meaning the race will take him twice as long as the other competitors.
Patrick, who wants to study criminology and counterterrorism at Murdoch University, has raised more than $16,000 for Melanoma WA ahead of the race and has been championing sun safety to his peers. His goal is to raise $20,000.
His girlfriend Tayla Johnson, 16, whose mother Sandra was diagnosed with melanoma in 2007 and died two years later, will be with hundreds of friends expected to cheer him on.
Patrick said he had seen how hard the death had hit Tayla's family and wanted to raise money for Melanoma WA.
He said the race meant a lot to his girlfriend and her family. "When I told her and her family, they broke down," he said.
Melanoma WA chief executive Clinton Heal said he was impressed someone as young as Patrick was trying to get other young people to think about sun safety.