Ryan Reynolds is mourning a dear fan who just lost his battle with cancer.

On Thursday, the “Deadpool” actor took to Facebook to share his condolences for Connor McGrath, 13.

>> Click here to see Reynolds' Facebook post

“For three straight years, my friend, Connor McGrath drop-kicked cancer… Not sure how… Maybe the cancer cheated… But the fight came to an end two nights ago,” Reynolds started the tribute.

Reynolds continued the post and revealed that it was the Make-A-Wish Foundation that brought the two unlikely friends together in the first place, and McGrath was given the opportunity to be one of the first people to see the uncut version of "Deadpool."

“It was the Make-A-Wish Foundation that brought us together. I can’t thank them enough. Seriously. Thank you. Because of his wish, Connor was the first person to see Deadpool. I traveled up to Edmonton, Alberta to surprise him with a rough cut of the film. There were still huge sections with wires we hadn’t yet painted out, jokes which weren’t working (and still aren’t) and green screens. Connor didn’t seem to mind. And I’d never felt luckier to get to be Wade Wilson,” Reynolds wrote.

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After McGrath saw the film, Reynolds visited him and wrote that he had no idea that was the last time he would see the young man.

“I went back to Edmonton 6 weeks later and I wish I could say things were looking up. After my visit, I didn’t know if I was saying goodbye or see ya later. Sitting here now, I realize it was both. I’m grateful I got to orbit Connor’s world for a brief time. Grateful for the pages and pages of hilarious texts between us. Grateful to his parents for allowing Connor to spend time with a foul-mouthed child in the body of a 39 year old,” he wrote.

Reynolds encouraged fans to donate to the foundation and shared images of his time with McGrath, who had such a big impact on Reynolds’ life.

For three straight years, my friend, Connor McGrath drop-kicked cancer... Not sure how... Maybe the cancer cheated......

Posted by Ryan Reynolds on Thursday, April 28, 2016