While he was in Toronto teaching kids at WE Day about “choosing kindness,” 10-year-old Jacob Tremblay took some time to do something kind for himself, by visiting with patients from the craniofacial and cleft lip and palate programs at SickKids Hospital.

But it turns out, the Vancouver native’s new friends were actually previous pen pals.

In preparation for his role in “Wonder”, Tremblay reached out to the hospital for help in understanding what it’s like living with a facial difference. And the patients were eager to help, sharing their stories with Jacob in personalized letters they sent to him earlier this year. During his visit, Jacob and his mom Christine showed their gratitude for the letters, saving them in a binder.

In the film, based on the novel by R. J. Palacio, Jacob plays Auggie, a boy with Treacher Collins syndrome, whose enrollment in prep school showcases the cruel world of child bullying.

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“I had the best time at SickKids Hanging out with this group of amazing young people,” the young Oscar nominee told the group. “I read their letters in preparation to play Auggie and every day on set… they were with me during the fun scenes and the tough scenes, so it was special to finally meet them all in person. I will always be grateful for their stories they shared with me!”

Tremblay revealed he not only read their stories on set, but he shared them with his fellow actors and the author of the book and that everyone learned a lot from knowing their stories.

“It’s so great to meet someone who’s playing a person with a facial difference,” former SickKids patient Jade Laird-Umanetz said. “And to have it played so effectively and powerfully will be really great to see.”

With current SickKids patient Kate Atkinson agreeing, “It’s amazing that somebody so prominent wanted to know more about us.” Adding, “We’re just normal kids. But he has the platform to make a difference and spread a message about facial differences.”

Most of the patients are already huge fans of the novel and can’t wait to see the film when it hits theatres April 2017.