<p>Pop-rock innovator Billie Eilish on Sunday bested a packed field to win the Grammy for Song of the Year -- which honors songwriters -- for her hit "Bad Guy."</p>.<p>The 18-year-old beat veteran acts Lady Gaga, Taylor Swift and Lana Del Rey along with newcomers Lewis Capaldi and Lizzo to take home the coveted honor.</p>.<p>She shares the prize with her older brother Finneas O'Connell, her primary creative collaborator.</p>.<p>The pair were gracious onstage, with Eilish telling her fellow nominees: "I grew up watching all of you."</p>.<p>"We just make music in a bedroom together," said O'Connell. "We still do that and they let us do that. (...) This is to all of the kids making music in your bedrooms today -- you're going to get one of these."</p>.<p>Eilish was among this year's most nominated artists with six nods, and is the youngest person ever nominated in all four of the top categories.</p>.<p>Best song was her second award of the night. She won earlier for best pop vocal album for "when we all fall asleep, where do we go?"</p>.<p>Before she released the album in March 2019, Eilish had already assembled a fervent online following for her bold, often haunting pop sound.</p>.<p>In August, Eilish became the first musician born in the 2000s to top the Billboard Hot 100, when she dethroned Lil Nas X, who spent a record-breaking 19 weeks at the top with viral hit "Old Town Road."</p>.<p>The artist named Billboard's 2019 Woman of the Year has also written and will perform the theme song for the upcoming James Bond film "No Time To Die."</p>.<p>"I feel like I'm not supposed to be here," she told E! television on the red carpet before the gala. "Life is weird."</p>
<p>Pop-rock innovator Billie Eilish on Sunday bested a packed field to win the Grammy for Song of the Year -- which honors songwriters -- for her hit "Bad Guy."</p>.<p>The 18-year-old beat veteran acts Lady Gaga, Taylor Swift and Lana Del Rey along with newcomers Lewis Capaldi and Lizzo to take home the coveted honor.</p>.<p>She shares the prize with her older brother Finneas O'Connell, her primary creative collaborator.</p>.<p>The pair were gracious onstage, with Eilish telling her fellow nominees: "I grew up watching all of you."</p>.<p>"We just make music in a bedroom together," said O'Connell. "We still do that and they let us do that. (...) This is to all of the kids making music in your bedrooms today -- you're going to get one of these."</p>.<p>Eilish was among this year's most nominated artists with six nods, and is the youngest person ever nominated in all four of the top categories.</p>.<p>Best song was her second award of the night. She won earlier for best pop vocal album for "when we all fall asleep, where do we go?"</p>.<p>Before she released the album in March 2019, Eilish had already assembled a fervent online following for her bold, often haunting pop sound.</p>.<p>In August, Eilish became the first musician born in the 2000s to top the Billboard Hot 100, when she dethroned Lil Nas X, who spent a record-breaking 19 weeks at the top with viral hit "Old Town Road."</p>.<p>The artist named Billboard's 2019 Woman of the Year has also written and will perform the theme song for the upcoming James Bond film "No Time To Die."</p>.<p>"I feel like I'm not supposed to be here," she told E! television on the red carpet before the gala. "Life is weird."</p>