Global superstar Dwayne "The Rock" Johnson has taken time out of his busy schedule to bring some sunshine into the life of a Moana superfan who is battling an aggressive form of cancer.

Johnson posted video to Instagram to bring some cheer to Hyrum Harris, who fighting acute lymphoblastic leukaemia which is complicated by Down Syndrome.

In the video he delivers a message to the young fighter, telling him to "stay strong" and thanking him for "inspiring everyone around you, including myself".

"This message is for a little boy out there, he's 3 years old, and this little boy is one of the coolest little boys around, and he's certainly one of the strongest because he is a fighter," Johnson says. "Right now, this little boy is in the fight of his life."


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The star went on to say: "His name is Hyrum Harris. Hello Hyrum, I hope this message gets to you.

"You don't know me, my name is Dwayne Johnson, I also go by The Rock and you're probably thinking, 'Of course you go by the name of The Rock because you have a head the size of a rock!'"

Johnson then reveals that Harris watches Moana "almost 10 times a day" because the character of Maui gives him strength.

"People tell me I kind of sound like him," Johnson said. "I just wanted to send you a video to tell you how much I love Maui too. I know a little of his song."

Johnson then launches into 'You're Welcome', a hit song from the film.

He finishes by saying: "I wanted to tell you, man, stay strong. There's another dude out there, me, Dwayne, who, like you, loves Maui too. There's no one like Maui. He's the coolest thing. I'm a big fan of Maui, too, and I'm a big fan of yours. Thanks for inspiring everyone around you, including myself. Stay strong, Hyrum."

After Harris and his family watched the video, Johnson returned to Instagram to share a note about the effect the video had on the young fighter.


The note read: "Joy and hope cost nothing, and yet it is the most powerful gift," saying that the video gave a boost to the whole family and medical team.

Harris' mother April told People magazine: "This has been such a moving experience for our family," adding that "every time Dwayne mentioned Hyrum's name, Hyrum pointed to his chest and in his soft sweet voice repeated saying, 'Hyrum,' as though he knew this was special for him," she added. "When he began to sing, Hyrum's eyes got very wide."