This story contains mild spoilers for the movie “Five Feet Apart.”
Dave Prager intends to watch the new movie “Five Feet Apart” hidden away in a corner of the theater where no one can watch him cry.
That’s because the young couple in the movie, portrayed by Cole Sprouse and Haley Lu Richardson, reminds him a lot of his late son and daughter-in-law.
In 2015, Katie and Dalton Prager became known around the world as “the real ‘Fault in Our Stars’ couple” after CNN wrote about their love story.
Like the couple in “Five Feet Apart,” Katie and Dalton had cystic fibrosis and pursued a relationship even though doctors forbid cystic fibrosis patients from standing less than 6 feet apart from each other, because they can share deadly infections.
Dalton and Katie did share an infection, and they died five days apart in 2016. He was 25, and she was 26.
“Dalton’s fear was that he’d be forgotten, so if the way the movie is telling this cystic fibrosis story, if it’s tied to Dalton in any way, that’s a blessing right there,” Prager said.
’A very human story’
Is “Five Feet Apart” inspired by the Pragers’ love story?
“The film is fiction and not based on the Pragers,” CBS Films, which produced the movie, wrote in an email. “The filmmakers did not meet nor engage with the Pragers, and the Five Feet Apart story and script is not based on them or their family.”
He added that “the initial spark” for the movie “was born from a conversation with Claire Wineland, who would go on to serve as medical consultant on the film.”
Wineland, a social media star and inspirational speaker who started a foundation to support families living with cystic fibrosis, died of complications of a massive stroke in September soon after she received a lung transplant.
Her mother, Melissa Nordquist Yeager, says Wineland was aware of the Pragers’ story when her friend, actor and producer Justin Baldoni, approached her in January 2017 about making a movie about two young people with cystic fibrosis.
“Absolutely, Claire was following Dalton and Katie’s story,” Yeager said. “It was a cautionary tale but also a very human story. Who can help falling in love with who they fall in love with?
“There’s a piece of their story in the movie,” she added.
Yeager remembers how the cystic fibrosis community, which is relatively small, lived through the ups and downs of Katie and Dalton’s story.
“We were all cheering them on when he got his lung transplant and then she got hers. We all had high hopes,” she said.
However, Yeager noted some major differences between the Pragers’ story and the couple in the movie. For example, Stella Grant and Will Newman, the fictional couple, meet at the hospital and at first are antagonistic toward one another.
The Pragers met on Facebook and fell in love almost instantly. Katie wanted to meet Dalton in person, even though she knew that he had Burkholderia cepacia, a life-threatening infection for people with cystic fibrosis.
“I told Dalton I’d rather be happy – like really, really happy – for five years of my life and die sooner than be mediocre happy and live for 20 years,” Katie said.
Dalton drove in from Missouri to meet Katie in Kentucky.
“My heart was racing, but I just went right up to him and hugged and kissed him on the mouth without even saying hello,” she said in 2015. “I’m usually not that kind of girl, but it just felt so right.”
Dalton and Katie both received lung transplants. He lived for two years with his new lungs, and Katie for about 14 months.
Will and Stella’s Hollywood love story has a more upbeat ending than Dalton and Katie’s real-life love story.
Despite these differences, Yeager says there are aspects of Katie and Dalton’s lives, as well as the lives of other people with cystic fibrosis, in the movie.
She hopes that gives Dalton and Katie’s parents some comfort. “I hope they can take pride knowing that their children’s story contributed to making a major motion picture in ways that very few people can,” she said.
Katie’s mother cries when she hears that Wineland, the consultant on the film, was aware of her daughter’s story.
“It’s just really overwhelming to think that Katie, coming from this little town in Kentucky, could touch so many people,” Debra Donovan said.
She remembers how her daughter loved to help others, even mailing colorful drawings and sweet notes to sick children she read about online. Katie would be happy to know that she was, even in a small way, an inspiration for a movie that brings attention to cystic fibrosis.
“I think if she knew about all this, she would feel like she didn’t waste her life,” Donovan said.
Donovan doesn’t plan on seeing “Five Feet Apart” anytime soon. It’s too emotionally difficult.
Dalton’s father isn’t sure when he’ll see the movie, but he knows he’ll bring that box of tissues.
Get CNN Health's weekly newsletter
Sign up here to get The Results Are In with Dr. Sanjay Gupta every Tuesday from the CNN Health team.
In the meantime, it’s enough for him to know that Dalton might have played even a small role in a movie that educates people about his son’s disease. He remembers how his son was bullied in high school for being short and skinny and having coughing fits. Maybe this film could make a difference.
“I’m sitting here right now with a big smile on my face knowing that he did touch people’s lives,” Prager said.
CNN”s Jessica Ravitz and John Bonifield contributed to this report.