"I was born with it, it's a genetic bone condition, it affects pretty much every bone in the body, specifically the skull and the jaw, and the clavicle,' Gaten said of his condition, which is known as cleidocranial dysplasia.
The 15-year-old added that it was this condition that helped him land his breakout role in Stranger Things.
"I was stretching in the audition room, just stretching," he said. Then he demonstrated how his shoulders can touch in the front because of how the condition affects his collar bone.
"[They said] 'What did you just do?' I said 'What? I'm stretching,'" Gaten continued. "I started explaining what it was. They liked how I told them about that and once I got the part they said they were gonna incorporate that and kind of use it in a realistic way. They asked if it was okay if the kids in the show had bullied me because of it. I said it's totally cool, it's realistic."
"They wanted to make sure each character in the show was unique," he said, "and they had something that was realistic and personal and made them not cookie cutter."
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