When a young boy's knee swelled up, the last thing he was expecting was for a live snail to be inside.

Paul Franklin was playing while on a family vacation, when he fell and scraped his knee, CBS 2 Los Angeles reported.

"We cleaned it up, put a Band-Aid on it," his father, Ken Franklin, told CBS. The boy's parents didn't think the cut would be anything serious.

"Before you know it, a couple weeks later, his knee was very swollen and infected," Ken said.

Paul's parents took him to the doctor and he was prescribed antibiotics to treat the infection. His physician was concerned that Paul might have a strain of Staph.

"I came home and his knee was the size of an orange and hot to the touch and he's limping. And I'm like, okay, we have to go to urgent care," Paul's mother, Rachael Franklin, said.

Despite the medical care, the wound did not completely heal. Rachael noticed part of the wound was turning black.

Rachael decided to drain the swollen wound, but was shocked to notice something hard and rock-like under Paul's skin.

"I put it on a paper towel and I'm like, 'That is a weird looking rock. It has swirls on it.' And I turn it over and it is a sea snail," she told CBS.

Rachael discovered the snail was still alive when she put it in water and saw it move.

She has since contacted marine biologists to see how such an event could be possible, the Daily Mail reported.

Paul named the snail "Turbo," and keeps it in a tank with his beta fish Dory.

"I just had to laugh because we were going through this three-week ordeal," Rachael told CBS.

Paul's parents said the wound on Paul's knee is almost completely healed.

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