Thousands of people followed Esther Earl's story online as she battled thyroid cancer, but for Elon freshman Alexa Lowey, her battle was even closer to home.

Esther and Lowey had been best friends since first grade, and when Esther was diagnosed with cancer at the age of eleven, Lowey didn't know what to do. "You can't really wrap your head around it at first," she said.

While going through treatment, Esther sought friendship in the online community.

She started out on fansites discussing her love of Harry Potter, then she began vlogging about treatment, and eventually her YouTube videos caught the attention of young adult author John Green.

"She just blew up on the Internet," Lowey said. "She's not like a celebrity but kind of a celebrity, I guess."

After Esther's death in 2010, Green helped her family create a book in her honor.

It debuted at No. 7 on the New York Times Best Sellers list. The book, This Star Won't Go Out, was a compilation of Esther's journal entries and notes from her friends and family.

"The coolest part for people who don't really know her is [that] the introduction is written by John Greene," Lowey said.

"It's heart wrenching, it makes me cry every time I read it."

Esther's story also inspired Green to write the novel, The Fault in Our Stars, which he dedicated to her. "It's really cool because like everybody reads the book, and I'm able to say, 'See that dedication? I know her, she's my best friend,'" Lowey said.

Esther's legacy also lives on through the This Star Won't Go Out Foundation, which her family and friends founded. The foundation has raised hundreds of thousands of dollars to help families with kids with terminal illnesses.

Lowey thinks Esther never would have imagined having such an impact, but she thinks Esther would be proud of the difference she has made.

"I think we would probably just laugh about how crazy everything is right now," Lowey said.

"She has a book dedicated to her like she's kind of a big deal. I think she wouldn't believe it and think it was absolutely ridiculous, but she'd be very happy."

Lowey continues to honor Ester's memory. This year, Lowey will serve as a team captain for Relay for Life raising money for cancer research in Esther's memory.