On the day Wonder — the big-screen adaptation of the best-selling novel about a young boy with facial differences because of a rare genetic condition — premieres, 20/20 is telling the story of a real-life “Wonder Boy” named Nathaniel, who was born with a similar craniofacial disorder called Treacher Collins syndrome.

In a preview for the Friday, Nov. 17, episode of 20/20, Nathaniel’s parents open up about how they were able to cope with their son’s physical differences. “It took me about a year [not to flinch when I looked at him],” his mother, Magda Newman, says in the clip. “A year, I almost cried every day. Every single time I looked at him, I could not believe [it was] my child. I couldn’t believe it.”

Despite Nathaniel’s diagnosis, Magda and her husband, Russell Newman, promised to raise their baby as a “normal boy.” The Nevada-based couple, who used to live in NYC, also explain how their first few months of parenthood were particularly trying. “We’d be walking with the stroller and everybody goes, ‘Oh, you have a baby!’ They go, ‘Let me see the baby!’ And then they go, ‘God, bless you,’” Magda recounts. “That was the worst, you know, as a new mother. Nobody would say, ‘Oh, he’s so cute. Congratulations.’ [They’d say], ‘Oh my God, what happened?’”

According to Russell, Nathaniel knew he was different from a very young age. “Definitely around age four or five, he could clearly vocalize, ‘I don’t like the staring, I don’t like the name-calling,’” he says of his child. “At that age, we’re going to birthday parties and other kids see him and scream and leave. He knows it was about him.”

To keep their spirits up, Nathaniel's mom and dad often listened to Christina Aguilera’s 2002 single “Beautiful,” and focused on the song’s poignant lyrics: “You are beautiful / No matter what they say / Words can't bring you down / You are beautiful / In every single way / Yes, words can't bring you down.” The producers of 20/20 surprised the Newman family with an appearance from the pop star, 36, who performed the Grammy-winning hit — which they still play every year on Nathaniel's birthday — live for them. Watch the heartwarming moment in the clip below.

Like Nathaniel, Jacob Tremblay’s character in Wonder, Auggie Pullman, faces adversity because of his physical appearance. In a recent interview with People, the 11-year-old actor revealed that he spent time with kids with facial differences to prepare for the part. He also detailed the two hours of makeup and prosthesis he underwent daily to transform for the role.

“[I had to wear] a neck piece, the main face piece, a helmet connected to an eye mechanism which pulled my lower eyelids down, a wig, contact lenses, and dentures,” he said. “It was pretty uncomfortable, but I didn’t mind.”

Wonder hits theaters on Friday, Nov. 17. 20/20 airs on ABC Fridays at 10 p.m. EST.