Daniel Downing may not be around to see Deadpool 2 when it's released next year, but the young fan has already been given a behind-the-scenes peek thanks to star Ryan Reynolds.

Downing, a five-year-old from Plympton, England, is suffering from an aggressive cancer called pontine glioma, which has left an inoperable tumour in his brain.

After Reynolds learned of the boy's condition, he took some time from the superhero sequel's Vancouver shoot for a one-on-one chat with his tiny admirer – part of which was filmed by Downing's father.

"How you doing, little buddy? Is everything going alright over there?" Reynolds asks in the video.

"I've been poorly," Downing replies.

After complimenting the boy on his Deadpool T-shirt, Reynolds asks whether he's seen the first Deadpool movie, which is rated 14A for violence and nudity.

Downing's parents appear to have made an exception, though; he answers that he's seen it "loads."

"You're a little young," Reynold says nervously, which gets a laugh from the boy's father.

Using video chat, the star then takes Downing on a virtual tour of the Deadpool 2 set.

The little boy's mother, Stephanie, said the family is "eternally grateful" for the personal call, which was just what her son needed to lift his spirits. 

"I'm so happy for Daniel," she told the Plymouth Herald newspaper. "It's something he wouldn't normally have been able to do and he was so excited. He told all his friends and his teachers. It's nice to see him so excited because he has been a bit down lately."

The median life expectancy for children with Downing's cancer is nine months after diagnosis. Deadpool 2 is scheduled to be released in June 2018.

Reynold’s video chat isn't the first time he’s has made a young superhero fan's day: earlier this month a B.C. boy recreated a viral image of Deadpool taken on Vancouver Island, and the star shared it with his 13 million Instagram followers.