Western Australia Water Police, local marine rescue volunteers and a rescue helicopter joined in the search.
Naturaliste Marine Rescue commander Paul Bresland confirmed the teen’s mother and siblings were found clinging to an inflatable paddleboard 14km offshore at 8.30pm, ABC Australia reported.
“He swam in, he reckons, the first two hours with a life jacket on,” he said, describing the teen’s efforts as “superhuman”.
“And the brave fella thought he’s not going to make it with a life jacket on, so he ditched it, and he swam the next two hours without a life jacket.
“I thought, ‘mate, that is incredible’.”
Bresland said the teen’s accurate description of the colour of the watercraft helped rescuers locate the stranded family within an hour.
He also paid tribute to the mother, acknowledging her tenacity throughout the ordeal.
“She’s an absolute hero as well.
“To keep those two children together and not give up is absolutely incredible.
“Physically, she just said, ‘I’m struggling, I can’t,’ but she just said, they’re looking her in the eye, and she just kept going and kept them together.”
South West Police Inspector James Bradley said the teen “cannot be praised highly enough, and that his determined and courageous efforts saved his family’s lives.
ABC Australia reported the family were taken to Busselton Health Campus after initial checks by paramedics.
They were later discharged from hospital and were understood to have visited the teams involved in their rescue to convey their thanks.
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