Who is singer Billie Eilish? 5 facts you don’t know

New teen sensation Billie Eilish scored a dream debut with “When We All Fall Asleep, Where Do We Go?” her album that opened at No. 1 this week.

As the 17-year-old alt-pop singer — part Lorde, part Lana Del Rey — heads to rock Coachella this weekend, here are five things you need to know about her.

1. She’s made 21st-century history

With huge first-week numbers second only to Ariana Grande this year, Eilish has become the first artist born in the 21st century to notch a No. 1 album on the Billboard 200.

2. She’s got big brother watching

Eilish’s older brother Finneas, 21, has got her back — in the studio and onstage. The multi-instrumentalist produced and co-wrote his little sister’s album, which the siblings worked on at their childhood home in Los Angeles.

3. She’s got some famous fans

Eilish’s celebrity superfans run the gamut from Shawn Mendes and Julia Roberts to Dave Grohl, who recently compared her with his legendary, Kurt Cobain-led band: “The connection she has with her audience is the same thing that happened with Nirvana in 1991.”

4. She’s dope, but she’s anti-drug

On “Xanny,” a hauntingly creepy highlight of her new LP, Eilish just says no to drugs: “I don’t need a Xanny [Xanax] to feel better/On designated drives home/Only one who’s not stoned.” In fact, she told the Guardian, “I have never done drugs, I’ve never got high . . . It’s just not interesting to me.”

5. She’s still addicted, though — to “The Office”

On the slinky track “My Strange Addiction,” Eilish reveals her obsession with the 2005-13 NBC sitcom “The Office.” The song samples dialogue from “Threat Level Midnight,” an episode from the series’ seventh season.