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'It Ends With Us' Author Addresses Controversy Over Casting Blake Lively + Justin Baldoni

Author Colleen Hoover has heard fans' concerns over the casting of the film version of 'It Ends With Us.'

Actors Blake Lively and Justin Baldoni are currently filming the movie adaptation of Colleen Hoover's hit book It Ends With Usbut some fans of the romance novel have been critical of the casting choices for the beloved story. According to Hoover's website, the novel follows the love story of Lily, a recent college graduate, a Ryle Kincaid, a neurosurgeon in her new city of Boston. The casting controversy stems from fan observations that Lively, 35, and Baldoni, 39, are much older than their fictional counterparts, who are written as 23 and 30, respectively.

Hoover heard these fan concerns, and at a recent appearance at her Book Bonanza festival, she explained that the decision to cast actors who are older than the book characters was intentional.

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

Hoover added that she later realized she "messed up" by making the book characters so young, and she is fixing that error in the movie.

"I didn't know that neurosurgeons went to school for 50 years," she says. "There's not a 20-something neurosurgeon."

"As I started making this movie, I'm like, 'We need to age them out because I messed up,'" she added. "So, that's my fault."

Fans also expressed concern over some of the outfits Lively's character has been wearing while on set. If Hoover has one tip for fans to quell their concerns, it's to simply trust the process.

"I don't remember describing outfits at all," she says."I don't care what they have on. In my head, it's about the conversation they're having and the story."

Hoover further comforted concerned fans by telling them they are going to be "so happy" with the result of the movie. The author also shared that she has even found herself crying on set while watching back footage of the film.

"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," she says.

READ MORE: Colleen Hoover Fans Have Thoughts About Who Should Have Been Cast in 'It Ends With Us'