A 13-year-old boy has been credited with saving the lives of his mother and two younger siblings by swimming for hours after the family was swept away by the sea off the Australian coast.

Austin Appelbee swam four kilometers to shore to raise the alarm after getting into trouble with his mother Joanne Appelbee, 47, brother Beau, 12, and sister Grace, 8, on Friday, police said.

Austin said he first went to get help in an inflatable kayak that was taking on water. He abandoned the kayak and then took off his life jacket because it was interfering with his ability to swim.

He said he tried to focus on positive thoughts as he swam for about four hours through choppy seas to shore, raising the alarm at 6 p.m.

“The waves are huge and I don’t have a life jacket on. … I just kept thinking, just keep swimming, just keep swimming,” Austin said Tuesday. “And then I finally got to the shore, fell to the bottom of the beach and just collapsed.”

The family, from the capital city of Perth, were on holiday using kayaks and paddleboards hired by their hotel around midday when rough ocean conditions and winds began to blow them out to sea.

A search helicopter found the mother and two children wearing life jackets and clinging to a paddleboard at 8:30 p.m., police said. They drifted 14 kilometers from Quindalup in the state of Western Australia, after spending up to 10 hours in the water.

“The actions of the 13-year-old boy cannot be praised enough – his determination and bravery ended up saving the lives of his mother and siblings,” said Insp. James Bradley said.

‘One of the hardest decisions’

Joanne Appelbee told reporters Tuesday that she sent her oldest child for help because she couldn’t leave her three children behind.

“One of the hardest decisions I ever had to make was telling Austin, ‘Try to get to shore and get help. This could get serious very quickly,'” she told the Australian Broadcasting Corp.

She said she was confident she would make it to shore, but was filled with doubt because the sun had set and help had not arrived.

“We were positive and we sang and we joked and … we treated it like a game until the sun started to set and then it got very wavy. Very big waves,” she said.

All three were shivering, and Beau had lost feeling in his legs from the cold by the time they were rescued, the mom said.

“I have three babies. All three made it. That was the only thing that mattered,” she said.

All four members of the family were medically examined, but none of them required hospital admission.

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