AUSTIN, Texas — Here's what you should know about Billie Eilish: young people love her.

Even before taking the stage Saturday evening at the Austin City Limits Music Festival, Eilish drew a packed crowd at the Bonus Tracks stage when she sat down for an "All Things Considered" segment for NPR

But that crowd was nothing compared to the one for her 6 p.m. set at the Honda stage. 

It was people as far as the eye could see, many under the age of 22 and with an emphasis on teen girls with glitter on their temples. 

Some of the kids in the crowd didn't look a day over nine.

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Eilish, a teen herself, was dressed in her signature style of baggy clothes, chains and technicolor hair and nails. She bounced around the stage, whispering over the heavy beats of her songs, pausing occasionally to let the crowd take the vocals – which they were extremely prepared to do – or banter, like when she told everyone, "I keep burping up Chipotle."

Eilish has a youthful vibe that clearly resonates with her audience. She was even able to get them to start a mosh pit during "you should see me in a crown." When she went out to the barricades, grabbing hands and leaning into the sea of people, the screams were ear-splitting.

It was hard not to feel approximately 1,000 years old during Eilish's set – but it was also kind of refreshing. Eilish's songs are catchy and have universal appeal, but it's special to see a pop star so in touch with her audience and vice versa.

Teenagers have always been at the helm of what direction pop music goes in. Eilish is just dictating it from the inside. 

If you missed Eilish during Weekend 1, she's playing again during Weekend 2.

Check out full interview with Eilish's brother, FINNEAS, below:

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