In 2010, at age 19, Sam Ballard from Sydney, Australia had his entire life ahead of him.

The college student and rugby player was a healthy and happy teenager, until a fateful night in his backyard would change his life forever.

Now, eight years later, Ballard's family are saying goodbye to the man who never stopped fighting as he battled a rare and unusual condition.

A Deadly Dare

The turning point in Ballard's life came when a friend noticed a slug crawling across the garden, and dared him to eat it.

"We were sitting over here having a bit of a red wine appreciation night, trying to act as grown-ups and a slug came crawling across here," remembered Ballard's friend Jimmy Galvin in an interview with The Project.

"The conversation came up, you know. 'Should I eat it?' And off Sam went. Bang. That's how it happened."

It was just a harmless joke at first. But days later, Ballard began to experience leg pains, followed by dizziness and vomiting.

The teenager actually told his mother Katie the symptoms might have been caused by the slug, but she couldn't believe it.

"No one gets sick from that," she told him. In fact, Ballard already had.

The teenager had contracted a rare parasite called rat lungworm, which can damage the brain and spinal cord.

Despite the name, rat lungworm is also often carried by garden mollusks like snails, and slugs.

The parasitic infection triggered another infection of the brain, which left Ballard in a coma for 420 days.

When he awoke, the once athletic young man was now paralyzed, and had to rely on help from his mother or caretakers to use the washroom and feed himself.

"On Friday, Sam passed away, surrounded by his family and loyal, loving mates."

Ballard lived the rest of his life relying on round-the-clock care, but in spite of the damage to his body Katie noticed that he was slowly recovering in recent years.

"Physios had Sam standing in the frame at the gym," she once wrote on Facebook. "He spent the afternoon laughing at me as I read him the sports section of the newspaper with new glasses on."

And she insisted that her son was "still the same cheeky Sam, and laughs a lot."

While a tragedy like this might make some parents resentful, Katie did not hold a grudge against the friend who dared her son to eat the slug.

"As far as I'm concerned he didn't do anything wrong," she explained. "It's just a silly thing. Just because you were being mates and doing things together "” it's not your fault."

Galvin also apologized to Ballard in person for the silly mistake, and said his friend "just started bawling his eyes out."

Lisa Wilkinson, a reporter who had previously covered Ballard's case, broke the news that he had passed away last week.

"On Friday, Sam passed away, surrounded by his family and loyal, loving mates," she said. "His last words to his mum: 'I love you.'"

[H/T: People, 10 Daily, News.com.au]

Rest in peace Sam.