'It Ends With Us' Author Addresses Controversy Surrounding Casting of Blake Lively and Justin Baldoni

"We need to age them out because I messed up," author Colleen Hoover said of the characters in the film adaptation

Colleen Hoover is clearing the air.

At Book Bonanza, the New York Times bestselling author’s annual book festival, Hoover spoke about the upcoming movie adaptation of It Ends With Us — and addressed some of the controversy surrounding the film.

The movie is based on Hoover’s 2016 novel of the same name, which, according to a synopsis on her website, follows Lily, a recent college graduate who moves to Boston and falls in love with Ryle, a neurosurgeon with a “no dating” rule. As the two grow closer, Lily’s first love, Atlas, comes back into her life and threatens what they have built.

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Since announcing that Blake Lively and Justin Baldoni will play Lily and Ryle in the film on Jan. 26, Hoover has faced backlash because of the significant age discrepancies between the actors and their It Ends With Us characters.

Lively, 35, is over a decade older than the 23-year-old protagonist. Similarly, Baldoni, who is also directing the book-to-screen adaptation, is nine years older than his 30-year-old book counterpart.

Now, five months after their casting, Hoover has an explanation for the age gap.

“Back when I wrote It Ends With Us, the new adult [genre] was very popular,” she said at the June 23 festival, according to Today. “You were writing college-age characters. That's what I was contracted to do.”

The author continued, “I didn't know that neurosurgeons went to school for 50 years. There's not a 20-something neurosurgeon.”

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Hoover viewed the adaptation as an opportunity to remedy her error. “As I started making this movie, I'm like, ‘We need to age them out because I messed up,’” she said. "So that's my fault."

The author also said she is “extremely happy” with the cast, especially Lively, who Hoover said she has been “obsessed” with since her turn as Serena van der Woodsen on Gossip Girl.

Despite this, the self-described pessimist said she hasn’t allowed herself to “get truly excited” about Lively joining the cast — or anything else — because something bad could happen. “It's not done filming,” Hoover said at the festival, according to Today. “Anything could go wrong.”

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As for fans who are, as Hoover phrased it, "upset about outfits and whatnot,” her advice is simply to wait until the film hits theaters.

Though she said she “loves” the costuming conversations that set photos from the film generated, she had a message for fans: "You've seen a couple of outfits that are completely out of context. I'm not worried about it.”

“I don't remember describing outfits at all,” the author told fans, per Today. "I don't care what they have on. In my head, it's about the conversation they're having and the story."

And when it comes to the story translating onscreen, Hoover said she was “blown away.”

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“I got to see the footage they filmed thus far,” she said, per Today. “I'm not a crier. I know that I write emotional books but I'm not an emotional person. And I cried so much on set.”

Hoover continued, "You guys are going to be so happy. I'm extremely happy and now my expectations are up and I'm going to keep them there."

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