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Directing a sci-fi blockbuster can be a rewarding experience for any movie maker. But when "Guardians of the Galaxy" director James Gunn found out that his character of few words -- Groot -- encouraged a child with a developmental coordination disorder to speak for the first time, he was astounded.

Josh Dunlap, a father to a child with dyspraxia, reached out to Gunn on Facebook to let him know how impactful "Guardians of the Galaxy" was on his son Sawyer.

Dyspraxia can affect children in different ways from making it hard to perform a sequence of movements like waving goodbye or brushing your teeth. Children who struggle with Oromotor dyspraxia have difficulty using mouth muscles to pronounce words and may have slurred speech.

"When Guardians came out Sawyer could only say about three words and would communicate to his mother and I by other means," Dunlap told Gunn on Facebook. "When he saw Groot, something clicked inside him and he connected with him on a level I haven't seen."

"He began to mimic him and he would use the word 'Bah' for a lot, but after he saw the film, he would change the tone in which he said it to convey a different meaning," Dunlap added. "He would also start saying Groot for many things as well. Since that, he was finally able to go to a speech class and it has helped amazingly."

Gunn responded to Dunlap on Faceback, "I love making movies because of stories like this. Thank you."