Dwayne Johnson is giving a sweet shout-out to a young fan.
The actor, 47, shared a video of himself on Instagram Monday, singing “You’re Welcome” from Moana to a 3-year-old boy with Acute Lymphoblastic Leukemia.
“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 in the video. “Right now, this little boy is in the fight of his life.”
He continues, “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 by the name of The Rock because you have a head the size of a rock!'”
“Hyrum, I know! It’s a thing, but it’s not really important right now. What is important is that I heard you love a movie called Moana, which is crazy because I love that movie too,” Johnson says. “I also heard you watch Moana almost 10 times a day because the character you love, Maui, gives you strength.”
The actor, who voices Maui in the 2016 film, adds, “People tell me I kind of sound like him. 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 proceeds to sing a few bars from the song, which was written by Lin-Manuel Miranda, Opetaia Foa’i and Mark Macina.
At the end of the video, the actor says, “I know you’re like, ‘Dude, leave the cool singing to Maui.’ You’re absolutely right, Hyrum. 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.”
Johnson’s video made it to Hyrum’s parents, April and Rich Harris, who were blown away by the actor’s kindness.
“This has been such a moving experience for our family,” April tells PEOPLE. “[Johnson’s] response was beautiful.”
April says the video couldn’t have come at a better time for her son, who “watched intently” as Johnson sang.
“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,” April adds. “When the reference of a head being compared to the size of a rock [came], Hyrum giggled. When he began to sing, Hyrum’s eyes got very wide.”
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“He looked at me,” April continues. “Smiled so big. Sang ‘You’re Welcome’ right along with the video. It was touching. Hyrum’s smile is infectious [and] healing to those that serve him and love him.”
Johnson’s video has left an impact on the Harris family, which includes six older children, she says.
“We were all touched that night and continue to be astonished and amazed at the outpouring of love and support my little fighter is receiving,” April adds. “The prayers matter. They carry us through when our days are rough and our nights are too short.”
A GoFundMe for Hyrum is available for anyone who wishes to donate and alleviate the family’s medical expenses.