The Avengers have all assembled for one extra special cause.
Chris Hemsworth, Mark Ruffalo, Brie Larson, Samuel L. Jackson and Ryan Reynolds have taken to social media to share their support for a young Marvel fan named Seb who recently underwent open heart surgery.
It all started on July 12, when Ivan Hollingsworth asked Twitter to help him contact the Earth's Mightiest Heroes to ask for their well-wishes as his son recovers from his recent operation.
"So here's a challenge Twitter-Sphere… How do we get a @MarvelStudios Superhero to send a message to our Heart Hero Seb?" he tweeted. "Recovering from open heart surgery and just so damn brave! Long shot I acknowledge, but I think he deserves it! Who's up for the challenge? #HeartHeroSeb."
His message soon caught the attention of one Dr. Bruce Banner. "I think we have some competition for the strongest Avenger, @chrishemsworth," Mark wrote. "Get well soon, Seb!"
As it turns out, Chris is in total agreement. "The strongest Avenger by far," the Thor: Love and Thunder star replied. "You are my heart hero, Seb."
Meanwhile, Brie, who will star in The Marvels next year, took a moment to make the young fan an official member of the superhero squad, adding, "Seb, welcome to The Avengers."
And Sam, who plays Avengers founder Nick Fury, added, "Assemble!! Speedy recovery wishes."
Although he hasn't officially made his on-screen debut in the MCU, it appears that Deadpool also has something special up his sleeve for Seb too. Ryan commented, "Can you open your DM's?"
In response to Chris' message, Seb's dad Ivan tweeted a photo of his son smiling in a field and gave an update on the boy's condition.
"We have Thor!" he wrote. "Thanks so much @chrishemsworth - this will mean the world to Seb. He's home now (4 days after heart surgery) and recovering well."