is opening up about his decision to honor costar late son Henry in the credits for

On Tuesday, Aug. 20, Reynolds, 47, shared a carousel of photos featuring him and his costar as he took a moment to share the reason why he honored Henry in the end credits of his latest film.

The actor began his post by praising Delaney's performance as Peter in the films, joking his character "may be the new anchor being," before touching on how his costar, also 47, has dealt with grief.

"There’s more to @robdelaney than some realize. He’s one of the most subversively funny people I know. He’s a beautiful, acerbic and vulnerable writer," Reynolds continued. "If you stayed through the credits of Deadpool & Wolverine, you might notice a credit saying, 'For Henry Delaney.' Henry is Rob’s son. And Rob lost his little boy to a brain tumor in 2018. Right as we finished Deadpool 2."

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Reynolds went on to say that he wished he'd placed a tribute at the end of

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