Evangeline Earl is a student at Green Mountain College and a volunteer with her family’s foundation, This Star Won’t Go Out, which provides financial support to the families of children with cancer.

At the New York City premiere of “The Fault in Our Stars,” the scene I found most difficult to watch was when 16-year-old Hazel, who has Stage 4 thyroid cancer, wakes up in the middle of the night gasping for breath. We see her father scoop her up and carry her to the car and then into the hospital, his desperation and terror and love and hope all evident in the grasp of his arms.

It brought me back to one night in 2008, when I watched my father carry my sister Esther from her bedroom to an ambulance stretcher. She was 14 at the time, struggling with thyroid cancer that had spread to her lungs. I was almost 17 and couldn’t imagine life without the person who understood me when no one else could, who looked up to me even as I sat in awe of her. My family huddled around her hospital bed while she was hooked up to all sorts of machines. We held hands and cried as we watched her lying there, so fragile, her eyes closed and her breathing labored. We didn’t think she’d make it through the night. Yet, like Hazel, she regained her strength. She lived for two more maddening, beautiful years — until just after her 16th birthday, in August 2010.

Hazel Grace Lancaster is not supposed to be Esther Grace Earl. Author John Green drew on a bunch of experiences, including his time as a children’s hospital chaplain, when creating the character in the “Fault in Our Stars” novel and film. But he dedicated his book to Esther. And he has said that her empathy, charm and snark helped inspire his work. “I could never have written The Fault in Our Stars without knowing Esther,” Green wrote. “Every word on that book depends on her.”

My older sister, Abby, and I were with Esther the weekend she met Green for the first time in person, at a Boston Harry Potter convention, LeakyCon 2009. He and Esther already sort of knew each other through Nerdfighteria, an online community of people adamant about “decreasing world suck.” And she and Abby chatted with him briefly, and took a picture, on the convention’s first night. But the next day, my usually confident little sister sat playing with her oxygen tank, shaking with nerves, when she saw him standing close by. “Go say hello!” I urged. Green’s rising fame — from his young-adult books and his Vlogbrothers YouTube channel — meant little to me. And I couldn’t quite understand Esther’s fascination with this tall, gangly guy. (Or with wizard rock bands — Draco and the Malfoys, anyone?) But I forced her out of her chair, and we walked over to him.

Shailene Woodley, center, plays Hazel Grace Lancaster in "The Fault In Our Stars." (James Bridges/AP)

They became friends after that. “It’s hard to isolate why, but I’ve never liked a teenager so much — at least not since I was a teenager,” Green, who is in his 30s, wrote in honor of her birthday two years after she died. “She was just really cool, in the best sense of the word. She never made me feel uncomfortable. She listened to me and responded thoughtfully, and was also happy to tell me I was full of s---.”

“I wish she’d read TFiOS,” he added. “I suspect she would’ve found it a bit far-fetched, but I do hope she’d have enjoyed it anyway. I’ll never know, though. I am astonished that the book has found such a broad audience, but the person I most want to read it never will.”

I’m not sure what Esther would have thought of it, either. But watching the movie, I couldn’t help feeling I was seeing my little sister on the screen. After a doctor proposes a new regimen of Zoloft and Lexapro, Hazel interrupts: “Why stop there? I’m like the Keith Richards of cancer kids.”

My sister could be similarly flippant. “This is an oxygen tube, and I stick it in my nostrils, which are located on your nose,” she explained in one video she uploaded to YouTube. “And then the long tube-y thing is connected to this big machine, which creates oxygen out of regular air. And that is a cool machine, and I like that machine, and I named that machine Denmark.”

In a lower moment of the movie, Hazel declares: “I also don’t want this particular life.” My sister occasionally expressed the same. “I sometimes wish I’d never gone through this,” she admitted in another YouTube video. “And then I realize that, if that happened, I wouldn’t be who I am, and then I get all, like, ‘Oh, that’s just confusing.’ But then sometimes I do wish it never happened: the cancer thing.”

Another parallel between Hazel and Esther: their fangirling of novelists. In “The Fault in Our Stars,” a wish granted by a nonprofit foundation takes Hazel and her love interest to Amsterdam to meet the author of Hazel’s favorite book, “An Imperial Affliction.” In July 2010, Esther’s wish through the Make-A-Wish Foundation brought Green and several other nerdfighters to visit us in Boston . We got rooms at the Marriott, ordered pizza, answered silly questions scribbled on a volleyball and laughed a lot. At one point, during a conversation about the idea of heaven, Green suggested that there were different ways to imagine an infinite afterlife. Esther was skeptical about his concept of infinite — a theme that recurs in “The Fault in Our Stars.”

Hazel is definitely different from Esther in some ways. Her appetite, for example. In one scene of the movie, we see her finish a multi-course tasting menu, with the barest traces of a chocolate dessert left in the tines of her fork. Before getting sick, my sister had a voracious appetite like that. She was always game to try local dishes in the countries we traveled to. She drank hot chocolate at all times of the day. And she’d finish off my meal when I was too full. After starting radiation and chemotherapy, and continuing with the experimental drug Sorafenib, however, her taste buds dimmed and she lost interest in food.

Sisters Evangeline, Esther and Abby Earl in Albertville, France, in 2005, before Esther was diagnosed with cancer. (Family photo)

“The Fault in Our Stars” is at its core a love story between two teenagers. My sister never got to have a relationship like that. She got to experience just a few weeks of being 16. Witnessing a life and a romance she could have had made me feel unbearably sad and yet, oddly, uplifted. It’s as if, through Hazel, my sister is able to continue having new experiences. As if she got a sequel.

I can vouch that my sister’s life was filled with other forms of love. Having a support group to bolster her, having an online community to socialize with, helped Esther to smile and press on. She was one of five siblings, all of us extremely close. (Whereas Hazel is an only child, texting below the dinner table while her parents carry on a conversation.) When Green promised to make Esther Day videos for my sister’s birthday each year, she asked him to make the day about “family and love.” Esther encouraged us as a family to never hesitate to say “I love you,” to express ourselves honestly, to hug and laugh.

In the spring before my little sister passed away, we drove to the cemetery where she would be buried. Our parents sat on a bench and talked while I pushed her wheelchair along the winding paths. We watched squirrels chase each other between the tall trees. She picked out the kind of tombstone she wanted. And we talked about death.

Like Hazel — who tells her mother that her “greatest fear is that when I’m gone, you’re not going to have a life anymore” — Esther was focused on what would happen to the people she loved. She wanted to know that we would be all right, that we would miss her and think about her, yes, but that we would move on with our lives and be happy again.

The last thing I remember Esther saying to me as she lay in her hospital bed was about my plans for that fall. Even in her last hours, she was selfless and loving. I was with her when she passed away, my hand in her hand.

E-mail Evangeline Earl: thisstarwontgoout@gmail.com

Esther Earl’s writing, along with photographs and essays by her family and friends, have been collected in the book This Star Won’t Go Out.

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