For 9-year-old Liam Doherty of Canton, Massachusetts, life hasn't always been easy.
"Liam was diagnosed with Crohn's disease when he was in kindergarten," said Liam's mom, Lauren Doherty.
"I just started Remicaid, which is like where I have a needle in my arm for like two hours," Liam said.
Crohn's is an autoimmune disease that attacks the intestines.
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The fourth grader sometimes has to stay home from school, skip field trips and miss ballgames.
"It was hard," Lauren said. "You don't want anything to be wrong with your kids, so when there is, it's pretty devastating."
When Liam was particularly down last year, his parents used it as a moment to motivate him to focus on the positives.
"We sort of used the saying, 'When life hands you lemons,' and he took it pretty literally, so sure enough, we have this lemonade stand," said Liam's dad, Russ Doherty.
The lemonade is just 50 cents, but Liam's customers have a habit over overpaying.
All the money raised goes to Massachusetts General Hospital, where his doctor is working on finding a cure for Crohn's.
"We're up to over $10,000 right now," Liam said.
This is truly a family affair – Liam's little sister, Rose, helped make the lemonade, and his grandmother made cookies.
"It's amazing that he is being such a courageous voice and such a good advocate for himself and for other kids in his situation," said Sue Young, a customer from Milton. "You get an unbelievable cup of lemonade and some homemade cookies."
Liam's parents couldn't be prouder of how their oldest son has turned a sour situation into something so sweet.
"He is dead set to fundraise and do everything he can until we find a cure," Lauren said.
"To be cured?" asked Liam, choking up. "I don't know, it would just be really cool to be cured and stuff."
Liam is helping doctors get there, one cup at a time.