Shailene Woodley, Ansel Elgort Say 'Thank God We Were Brother and Sister' Before 'Fault in Our Stars' (Video)

James Bridges
"The Fault in Our Stars"

Woodley noted why their 'Divergent' sibling dynamic was the key to their latest love story at a Q&A with Josh Boone, John Green, Nat Wolff, Laura Dern and Sam Trammell.

After popping up for a surprise Q&A at the first-ever fan screening of The Fault in Our Stars on Saturday night, director Josh Boone, author John Green and the cast came together at New York City's Crosby Street Hotel on Sunday afternoon for a live stream press conference, presented by Yahoo! and Tumblr -- during which Shailene Woodley noted that it was necessary to play Ansel Elgort's sibling in Divergent before becoming his terminally-ill lover in Fault.

VIDEO: 'Fault in Our Stars' Author: I Cried When I Saw Shailene Woodley On Set

"It wasn't that weird because I've always sort of wondered what it'd be like kissing my brother," she joked at first -- to which Nat Wolff said, "That's the best answer ever!" While she was initially shocked that they were reading together -- "the fact that two studios would allow that to happen is very rare" -- Woodley explained the relationship shift is not only part of the appeal of being an actor, but also said their onscreen Fault bond wouldn't have been possible without Divergent. "There's something really beautiful about working with someone and working with them again and again and again, because the more you get to know somebody on a personal level, the more free you feel artistically. I think that if Ansel and I hadn't known each other from Divergent, our relationship in this movie would not be what it is, because we didn't have to go through the rehearsal phase of getting to know one another, becoming comfortable with one another," to which Elgort agreed.

She continued, "There would be times when we'd disagree, and if we didn't know each other, we might not say we disagree, because there's that politeness. We were very open with one another when something wasn't going the way we envisioned. It completely lent to these characters … Thank god we were brother and sister, and now we get to spend the next four years together, which is pretty freaking rad," she said of the dystopian franchise's upcoming sequels. (Wolff then jokingly asked, "What are you guys doing?")

PHOTOS: Photos of 'Divergent,' 'Fault in Our Stars' Actor Ansel Elgort

Laura Dern and Sam Trammell highlighted Wolff's constant hilarity while filming, which was apparent throughout the panel. And Elgort said he was thankful for his co-star's off-screen comic relief. "I probably cried and laughed the most during those few months, just because during the day, I'd be crying my eyes out on set and so emotional, and then at night, I'd be sitting in my apartment with Nat, crying of laughter, because he'd make the most absurd joke ever, or we'd be at dinner and he'd just make a joke. I literally, one night, went under the dinner table to compose myself because I was laughing so hard, and the restaurant was very, I think, a little bit disturbed."

Boone noted that after seeing many actors for the role -- many who were closer to 16 years old –--he finally cast a persistent Woodley as the lead after she read the eulogy scene. "The first thing I thought after maybe a minute and a half was, 'Why did I make this so hard on myself?' "

As a teen, Woodley told the press audience that she would have identified much more with Elgort's Augustus than Hazel. "I always felt like, 'There was something to do in the world!' and 'How am I gonna change the world?' and 'What's my mission going to be?' " she said of Gus' outlook. "I think that's a very common theme when you're that age of trying to figure out who you are and what you're going to do with your life and to be remembered, to be important. I was so moved by Hazel and her ability to recognize, at such a young age, that it's not about that. She's the least narcissistic person that I've ever met in my life, which is why maybe she doesn't actually exist."

VIDEO: 'The Fault in Our Stars' Trailer: Ansel Elgort Reignites Shailene Woodley's Passion for Life

When the panel was asked about one of the film's taglines, "One sick love story," Green stated, "You will also notice that the tagline is not on the newest movie posters!" He elaborated on the goal of his book and their film: "We wanted to tell the story of people living with serious illnesses, living with disabilities, but show that people who are very sick are not fundamentally other from the healthy. It's not like they're less human than anyone else; they can have all of the love, joy, anger, passion as any other life, and to try to show people where disability is a big part of their life, but it's not the only identifying thing about them, to try to show the full humor and pathos of being alive, even if you're sick."

Trammell also commented on the general irreverence for their characters' cancer conditions: "I love how you have the characters not deify the disease and disrespect it in a way," with Wolff adding, "It's not melodramatic." Boone noted, "We met a lot of kids living with cancer, and the thing that validated that book for me the most was how similar they were to those characters -- how funny, cynical and philosophical they were."

The Fault in Our Stars hits theaters June 6.

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