Tom Holland's Brother Has Cameo In 'Deadpool & Wolverine'—And Ryan Reynolds Had No Idea

Warning: 'Deadpool & Wolverine' cameo spoilers ahead.

Ryan Reynolds missed the memo about fellow Marvel actor Tom Holland's younger brother Harry making a small cameo in Deadpool & Wolverine.

Holland, who played Peter Parker/Spider-Man in six MCU films, has two younger brothers, one of whom played a Deadpool variant in the sequel to Deadpool and Deadpool 2.

The unlikely superhero duo film starring Reynolds and Hugh Jackman as Wade Wilson/Deadpool and Logan/Wolverine, respectively, blew past the $500 million mark at the global box office over its opening weekend—an impressive feat for an R-rated film from Walt Disney Studios, no less.

The multiverse action film is rife with Easter eggs and features a countless number of cameos and character variants, making for a fun and riotous moviegoing experience for diehard Marvel fans.

So many familiar names were attached to the production, it's no wonder Reynolds lost count of who among his Hollywood cohorts made the cameo call sheet.

It wasn't until supervising stunt coordinator and second unit director George Cottle gave a shout-out to the younger Holland sibling on Instagram stories that Reynolds realized that Spidey's little brother was in the film.

Cottle noted Harry's involvement as part of the stunt team and shared a photo of the 25-year-old actor on set in his Deadpool variant costume, writing:

"When [director Shawn Levy] and [Reynolds] set the bar so f'ing high, even the stunt team needed a special guest star!!"

He added:

"It may not be the Holland the world wanted, but it was the Holland we all needed!! [Harry] you smashed it my friend!"

Cottle's note tagging Harry was followed by the hashtag #haroldpool.

Reynolds, who also co-wrote and co-produced the franchise's threequel, was surprised at the news and reshared Cottle's post, writing:

"This is how I find out? You tell me?"

@vancityreynolds/Instagram

Fans were here for Reynolds' response to the family affair excitement.

Harry, whose screen credits include his brother's films The Impossible and Cherry, reshared Reynolds' post and wrote:

"Lots of Cameos in Deadpool..."

In the third act of Deadpool & Wolverine, "Haroldpool" appeared as an alternate version of Deadpool for a gory yet comical battle scene in which Wade and Logan take on the army of Deadpool variants sent to destroy them through the portal by the villainous Cassandra Nova, played by The Crown's Emma Corrin.

Another cameo in the scene with the bloody Deadpool Corps smackdown included what the fandom speculated all along was Reynolds' wife, Gossip Girl actor Blake Lively, as Lady Deadpool.

Others who lent their voices for cameos in the same scene included Matthew McConaughey as Cowboy Deadpool; Reynolds and Lively's 7-year-old daughter, Inez, as Kidpool; Firefly actor Nathan Fillion as the floating head Headpool; and Paul Mullin, a soccer player on the Wrexham A.F.C. football team owned by Reynolds, as Welshpool.

Deadpool & Wolverine also featured special surprise appearances from former superhero actors including Chris Evans reprising his role not as Captain America but as his Fantastic Four character Johnny Storm / Human Torch; Jennifer Garner as Elektra Natchios from the Daredevil films; Channing Tatum's Remy LeBeau / Gambit, the titular character Tatum was supposed to play in an unproduced Gambit Marvel movie; and Wesley Snipes' vampire hunter from the Blade franchise, which is in the process of a struggled reboot that prompted Snipes to throw shade.

Tyler Mayne and Aaron Stanford, who played Sabretooth and Pyro, respectively, from the 20th Century Fox's X-Men series also appear in the film's 127-minute running time.

While Tom Holland does not appear in Deadpool & Wolverine, Reynolds and Logan star Hugh Jackman expressed interest in working with him on another project.

Reynolds told Marvel Thailand, per Entertainment Weekly:

“If I could pick one, I’d love to play with Spider-Man. Tom Holland is amazing."

Jackman agreed and joked:

“I agree. He’s so cool. That would be great. And he’s young."

"We could pile on him and abuse him. You know, just yell at him.”

Deadpool & Wolverine, currently dominating the worldwide box office, features additional appearances from Chris Hemsworth, Jon Favreau, Henry Cavill, and Logan alum Dafne Keen.