Earlier this month, Bridger Walker sustained serious injuries to his face and head while saving his four-year-old sibling from a charging dog.
According to his family, he underwent surgery that lasted around two hours and received more than 90 stitches.
After Chris Evans, who plays Marvel’s Captain America, sent a message to Walker, Downey Jr decided to one-up him.
“Bridger, you’re a rock star,” said Downey Jr in a video message to Walker. “I play Tony [Stark], that makes me an old friend of Cap’s. I heard he sent a shield your way: I’m going to do one better.
"You call me on your next birthday, I got something special for you. Late. By the way – that’s a promise; a promise beats a shield.”
Tom Holland, who plays Spider-Man, also spoke to Bridger on a video call and invited him to come to the set of his next film.
"If you ever want to come to set and hang out, and see the Spider-Man suit up close, and hang out with us, you're always welcome," Holland said. “I want to say you are so brave, mate. We are all so proud of you, and your little sister is so lucky to have someone like you."
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