They might spend their work days defending the galaxy, but off-screen the stars of The Avengers franchise have another role: super dad!
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Chris Hemsworth, who plays Thor in the superhero franchise (as well as his own series of films) and Iron Man Robert Downey Jr. sat down on the London set with ET's Brooke Anderson to talk about splitting their time between defending the galaxy and diaper duty.
"I'm telling you his superpower is parenting," Downey says of his co-star. "I have never seen anything like it."
Hemsworth, who has a two-year-old daughter and infant twin sons with actress Elsa Pataky, is quick to give all credit to his wife, but Downey, who welcomed his third child with wife Susan in November, thinks the hunky Australian has another secret to parenting success.
"Elsa's the greatest, but just seeing them come out to a brunch with a twin strapped on each of them, I just look and I think 'They're young. That's how they can do that,'" the Iron Man star jokes.
Their youngest kids are still too little to recognize their famous fathers’ A-list status, but Hemsworth admits that his daughter India has a knack for spotting her dad, even in full Asgardian getup.
"My daughter, I mean she's two, but she looks at the Thor action figure or in a magazine, she was like 'papa, papa,'" he laughs.
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Mark Ruffalo, who plays Bruce Banner/The Hulk and has three children with his wife Sunrise Coigney, told Anderson that his teenage son has even taken to the color green in tribute to his dad’s character.
"My son's hair is dyed green right now," Ruffalo confessed. "His clothes are green, his hair is green. I'd like to think it was because of me."
Captain America star Chris Evans is one of the few Avengers without kids of his own, and he told Anderson that family obligations prevent the cast from spending too much off-screen time together.
"It is a little bit trickier when you are working all day on set, when you get home a lot of people have responsibilities," Evans says.
But not to worry, the super stud jokes that his castmates' responsibilities don’t prevent him from having his own fun.
"I'm just sniffing out trouble on my own," he says. "My wife won't let me go with him," Ruffalo says with a laugh.
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Check out more behind-the-scenes footage from the set of Avengers: Age of Ultron in the video below.