Click here to read the full article. Robert Downey Jr. and Tom Holland have joined their “Avengers” castmates in speaking with 6-year-old Bridger Walker, who saved his younger sister from an attacking dog on July 9.Bridger’s aunt, Nicole Noel Walker, first caught the attention of Captain America actor Chris Evans with an Instagram post on July 12 in which she tagged several “Avengers” actors. Walker asked them to provide words of encouragement to Bridger, who suffered several bites to his head and required 90 stitches after protecting his younger sister.More from VarietyEver since, Walker has documented each conversation between the celebrities and Bridger via social media. On July 16, Walker shared that Evans had sent Bridger a video message in which he promised to give him an authentic Captain America shield, and now Downey Jr. and Holland have followed suit.In a video message to Bridger, Downey Jr., who plays Iron Man, attempted to one-up Evans’ gift.“Bridger, you’re a rockstar,” Downey Jr. said. “I hear [Captain America] sent a shield your way. I’m going to do one better, you call me on your next birthday. I’ve got something special for you.”Spider-Man star Tom Holland hopped on a video call with Bridger, who dressed up in full Spidey garb.“I want to say you are so brave, mate,” Holland said. “We are all so proud of you, and your little sister is so lucky to have someone like you.”Holland then invited Bridger to come to set during the filming of the next “Spider-Man” film.“We’re going to be shooting ‘Spider-Man 3’ and if you ever want to come to set and hang out and see the Spider-Man suit up close, you’re always welcome,” Holland said.Mark Ruffalo, Brie Larson, Robbie Amell and Grant Gustin also commented on Walker’s original post, commending Bridger’s bravery and calling him a real superhero.“People who put the well-beings of others in front of themselves are the most heroic and thoughtful people I know. I truly respect and admire your courage and your heart,” Ruffalo wrote. “Real courage isn’t dominating people or fighting against people or walking around like a tough guy. Real courage is knowing what is right to do and doing it even when it might end up hurting you somehow. You are more of man than many, many I have seen or known.”Best of VarietySign up for Variety’s Newsletter. For the latest news, follow us on Facebook, Twitter, and Instagram.