As a toddler, Sam was snapped on a beach with a determined expression and one fist clenched - an image that spawned the well-known "success kid" meme.
The image has been used widely online by people seeking to celebrate happy moments, small victories and good days.
Now eight, Sam's net fame is being used to raise cash for a kidney transplant for his father.
Sam's father Justin fell ill in 2006 and suffered total kidney failure in 2009. He has been on dialysis ever since. Mr Griner's mother died from the same disease.
In a week, the fund-raising campaign has won pledges of more than $93,000 (Â£63,000) - far more than the $75,000 needed to pay for the medical procedure.
Health insurance is covering some of the costs of Mr Griner's treatment but the family needs extra cash to pay for the operation and care to help him recover afterwards.
The Griner family are also using the fund-raising page to look for people who are a good tissue match and willing to donate a kidney.
In an interview with the Daily Dot, Sam's mother said a transplant was the only way to save her husband's life.
Ms Griner said she was initially sceptical about using her son's internet fame to raise money but realised it could be a good way to highlight the cause.
"We're the parents of 'Success Kid' for goodness' sake," Ms Griner told the news site. "If anyone understands the power, the mass, and goodwill of the internet, it's those of us lucky to experience it daily."
Other net famous people have also used their appearance in memes to raise cash for good causes. Laina Morris, better known as the face of the overly-attached girlfriend meme, has used her YouTube channel to highlight charities needing cash.
Sam Griner has gone from success kid to success kidney.