Transcript for 'Wonder' author R.J. Palacio tells the story behind her inspiration for the book: Part 3
Reporter: The first day of middle school, who ever wants to re-live that, but imagine what it's like for Nathaniel Newman. In the fall of 2015 Nathaniel walked into bd Billinghurst middle school in Reno, Nevada for his first day of sixth grade. Which for Nathaniel meant another brutal round of introductions. New school, new classmates. To ease the transition, the newmans had a plan. Russell came up with the great idea. They sat down together and we write a letter. My name is Nathaniel Newman and I am 12 years-old. I am different. I don't want you to be surprised when we meet. I -- I have a trach to breathe and a special hearing aid to hear. I have three dogs. I like pokemon a lot, as well as "Star wars." I really just want you to treat me like everyone else. And we include a picture to try and avoid some of the first day shock and awe if you will. Reporter: After a couple of months we came to visit Nathaniel at school. Ms. Culbertson and Ms. Urban are his 6th grade teachers. How important were those letters that Nathaniel's family sent out? The students knowing what to expect I think is very helpful, rather than just walking into school and then having that reaction, which most parents have taught their kids not to have that kinda reaction. But it's hard. They're kids. Were any of guys at all nervous to meet Nathaniel the first time? Yeah. Yeah, it's okay to admit that. Tell me why you were nervous. I was a little nervous because I didn't wanna say anything to hurt his feelings. I didn't know what -- what the experience would be like. He may look different on the outside. But on the inside, he's perfectly Normal just like everyone else. Reporter: But the single most powerful change in how children treat Nathaniel isn't because of that letter but because of a little blue book called "Wonder." We incorporate the book "Wonder" into the welcome letters. Like, hey, you might have read "Wonder" now. You might have read the book "Wonder." If you have than you already know a little bit about me. Reporter: "Wonder" tells the story of 10 year-old auggie Pullman born with a facial difference a lot like treacher Collins. Rj Palacio wrote the book after a chance encounter with a little girl who looked a lot like Nathaniel. Was in front of an ice cream store here in my neighborhood, with my two sons. And I realized that there was a little girl sitting directly next to me. She had a very severe cranial facial difference. And I kind of panicked, 'cause my little boy started to cry hysterically and in my haste to protect her from his reaction, I kinda like turned the stroller around, I started pushing it away really fast. It was terrible. And I -- I was so mad at myself for the way that I handled it. For the rest of the day, I just kept thinking about all the things I wished I'd said and done. Reporter: Palacio started writing with the hope that this story could inspire parents and children alike. I just thought, "Okay, I'm going to write a book and it's going to be about what it must be like to face a world every day that doesn't know how to face you back." Reporter: When the book came out in 2012 nurse pat chibaro was one of the first to read it. She immediately reached out to the newmans. I literally read it in three hours, cried the whole time. And I remember calling back pat and going, "Pat, did she spy on us? Like, this is freaky." And then we got to meet Raquel face to face for lunch one day. And when she saw Nathaniel, you could just see this look in her face. And I remember thinking, "Oh, my goodness, this is auggie Pullman come to life." Reporter: The similarities between the book and Nathaniel's life are almost unbelievable. "Wonder" begins with auggie starting at a new school just like Nathaniel, enduring dozens of surgeries like Nathaniel. And even more astonishing, if you flip to page 118 you'll even find the lyrics from that song that means so much to the newmans. A song they still play every year on Nathaniel's birthday. It's so remarkable that you wrote this entire novel and then you meet this family and it's the family in your novel. I know. I mean -- It was amazing. Reporter: Today "Wonder" is more than a book, it's a phenomenon selling more than five million copies and translated into 45 languages. It's even become required reading in hundreds of schools across the country. It's become part of a campaign, in essence, to be kind. I used this quote, "If you have the choice from being right or being kind, choose kind." Such a simple thing. That book has singlehandedly making life easier for children with facial differences. It's just a fact.
This transcript has been automatically generated and may not be 100% accurate.