Ryan Reynolds' latest movie Deadpool isn’t exactly kid-friendly, but that doesn't mean he can't be!

The 39-year-old actor posted a Facebook message on Friday in support for Connor McGrath, a 13-year-old Canadian boy who is undergoing cancer treatment at a hospital in Alberta.

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"Like Wade Wilson, Connor's trying to put cancer in his rearview mirror," the Deadpool star wrote, referring to his movie character's real name. In the film, Wilson undergoes treatment for cancer before eventually becoming a superhero.

"This is my friend, Connor McGrath. He's quite possibly the biggest ‪#‎Deadpool fan on earth," Reynolds wrote alongside a picture of the two together. "He was also the first person ever to see the Deadpool film."

Reynolds writes that he traveled to see McGrath in Edmonton, Alberta, six weeks ago to show the teen a special screening of the movie. He joked that McGrath connected with the foul-mouthed hero because Connor is "the funniest, potty-mouthed Canadian mercenary I’ve ever met."

The Canadian actor had a few potty-mouthed words of his own to issue -- in the form of a compliment!

"I know lots of celebrities jump up and down touting a cause -- and maybe I'm no different. But holy frozen s**t-slivers, I love this kid. He's the GREATEST," he wrote.

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Aww! We can feel the love!

Reynolds isn't the first Marvel superhero to bring some in-person joy to kids battling cancer. Last year Chris Pratt and Chris Evans teamed up to visit children in treatment for cancer near Boston, Massachusetts. Watch below to see how that went down.