Billie Eilish Says She's 'Pretty Confident' in Her Tourette Syndrome: 'It's Part of Me'

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Billie Eilish is getting candid about living with Tourette syndrome.

The Grammy Award winner, 20, acknowledged the neurological disorder as she had a tic while appearing Friday on the season 4 premiere of David Letterman's Netflix talk show, My Next Guest Needs No Introduction.

"I'm very happy to talk about it," she said, adding: "I actually really love answering questions about it because it's very, very interesting, and I am incredibly confused by it and I don't get it."

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"I never don't tic at all, because the main tics that I do constantly, all day long, are like, I wiggle my ear back and forth and raise my eyebrow and click my jaw ... and flex my arm here and flex this arm, flex these muscles. These are things you would never notice if you're just having a conversation with me, but for me, they're very exhausting," Eilish added.

She explained that she was diagnosed when she was 11 after having small physical tics as a kid, which were exacerbated when she was older. When she's "focusing" on tasks like singing or riding horses, she doesn't experience the tics as much.

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"It's really weird, I haven't talked about it at all. The most common way that people react is they laugh because they think I'm trying to be funny," she explained to Letterman, 75. "They think I'm [ticcing] as a funny move. And so they go, 'Ha.' And I'm always left incredibly offended by that. Or they go 'What?' And then I go, 'I have Tourette's.'"

"So many people have it that you would never know. A couple artists came forward and said, 'I've actually always had Tourette's.' And I'm not going to out them because they don't want to talk about it. But that was actually really interesting to me because I was like, 'You do? What?' " Eilish added.

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Eilish previously revealed her diagnosis with Tourette syndrome in 2018 after fans made video compilations of her tics, according to Billboard.

"It's not like I like it, but I feel like it's… part of me. I have made friends with it. And so now, I'm pretty confident in it," Eilish mused on My Next Guess.