Ryan Reynolds is paying tribute to someone very special.

The Deadpool actor shared the touching way he honored friend and  DeadpoolampWolverine costar Rob Delaney—who stars as mild-mannered Peter in the Marvel films—by dedicating Deadpool & Wolverine to Rob's son Henry, who died in January 2018 at the age of 2 after a battle with brain cancer.

"Rob Delaney brought PeterPool (née Sugarbear) into our hearts and effortlessly redefined the modern moose-knuckle—showing it can be chic AND practical," Ryan wrote on Instagram Aug. 19. "And if theories are correct, he may be the new Anchor Being."

But as the 47-year-old added, there's more to Rob that some might know as he's "one of the most subversively funny people I know."

"If you stayed through the credits of Deadpool & Wolverine, you might notice a credit saying, 'For Henry Delaney,'" Ryan continued. "Henry was Rob's son. And Rob lost his little boy to a brain tumor in 2018. Right as we finished Deadpool 2."

And while the Marvel start said he has always felt regretful about not including a tribute at the end of that film, he pointed out a silver lining that "even more people are seeing Henry's name in the credits of Deadpool & Wolverine," which recently passed a billion dollars at the worldwide box office.

He added, "And at long last, father and son are sharing the same screen."

Ryan—who shares daughters James, 9, Inez, 7, and Betty, 4, and son Olin, born in 2023 with Blake Lively—also took a moment to shoutout Rob's 2022 book A Heart That Works, which details the 47-year-old's journey through grief. Ryan called it "an incredible piece of writing which explores the kaleidoscopic colours of emotion Henry's passing revealed."

Since Henry's death, Rob has been open about the difficulties he and his wife Leah have faced, in addition to caring to for their other three sons—the youngest of whom they welcomed in December 2018.

"The things my wife and I had to learn to care for a one year old with a complex tracheotomy," Rob recalled on Instagram in 2021. "But I wish to hell I was still doing it every day. I miss caring for him. Our son Henry."

Henry—whose tumor was discovered shortly after his first birthday—underwent treatment to remove the tumor and received a tracheotomy due to cranial nerve damage, but he sadly passed on the morning of Rob's birthday in 2018.

Still, Rob is incredibly thankful to those that have reached out, especially since the publication of his book.

"The volume of letters and messages I've gotten from other bereaved parents and siblings is completely unbelievable," he shared on Instagram in January. "It feels very strange to not be able to reply to all of them."

The Catastrophe actor continued, "I want to say hello to all the bereaved parents and siblings who have written me and say that I love you."

"And doesn't it feel good and right to write about your dead child?" he wrote. "To say their name? To see it written down and send it off to someone else? To parent your child in some way, even though their body is gone? You love them. And they love you."

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