The artist's chart-topping track "Everything I Wanted" beat out a top notch roster of 2021 Grammys nominees, which included Beyoncé ("Black Parade"), Black Pumas ("Colors"), DaBaby and Roddy Rich ("Rockstar"), Doja Cat ("Say So"), Dua Lipa ("Don't Start Now"), Post Malone ("Circles") and Megan Thee Stallion ("Savage").
This marks Billie's seventh Grammy win and second this year.
The 19-year-old singer took to the stage with her brother and music producer, Finneas O'Connell, to accept the trophy. She dedicated her back-to-back award to Megan, who took home three awards earlier in the evening, winning in every category she was nominated in except for Record of the Year.
"This is really embarrassing for me," Billie said. "Megan, girl, I was going to write a speech about how you deserved this, but then there is like there is no way they will choose me, I was like it's hers."
She went on to praise the "Savage" singer, saying, "You deserve this. You had a year that I think is untoppable. You are a queen. I want to cry thinking about how much I love you. You are so beautiful. You are so talented."
Billie added, "You deserve everything in the world. I think about you constantly. I root for you always. You deserve it, honestly, genuinely, this goes to her, can we just cheer for Megan Thee Stallion, please."
After the applause, Billie went on to thank other idols and collaborators at the ceremony. "I really do appreciate this," she said in the speech. "Thank you to the Academy. Thank you to [presenter] Ringo [Starr]. I love you, I love my team, thank you for seeing me. Thank you to my brother Finneas."
Heading into Sunday night's ceremony, which took place for the first time ever at the Los Angeles Convention Center and was hosted by Trevor Noah, Billie nabbed four nominations. She ended up scoring the Grammy for Best Song Written for Visual Media for "No Time To Die" from the film.
She's the first person to win Record of the Year two years in a row since U2 accomplished the feat nearly 20 years ago, in 2001 and 2002. Roberta Flack became the first artist to win the category twice in a row in 1973 and 1974.
Last year, Billie swept the Big Four Award categories (and was the youngest to do so) for When We All Fall Asleep, Where Do We Go? and the track "Bad Guy."
For the 2021 show, the fashion and music icon was nominated for Song of the Year, which went to H.E.R. for "I Can't Breathe," and Best Pop Solo Performance, which went to Harry Styles for "Watermelon Sugar."
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