Billie Eilish's mother finds her success "mind-blowing".
Actress Maggie Baird - whose 18-year-old daughter collaborates with older brother Finneas O'Connell, 22, on her hugely popular tracks - revealed she will "never" get used to seeing the 'Bad Guy' hitmaker become a global superstar.
She told 'Late Late Show' host James Corden: "People are like, 'How does it feel that she's singing at Radio City?'
"Like, it blew my mind when she sang at the Hi Hat. It blew my mind when I sat here and heard Billie and Finneas play a song.
"It's never not been mind-blowing. So it's almost been like four years of, 'Oh my God.' "
Corden spoke to the 'Life Inside Out' actress as he had Billie on his show for a special edition of 'Carpool Karaoke' which saw them stop off at her home.
Sitting in her brother's bedroom, the teenage star said: "Before we made any songs together, Finneas said [something], kind of as a joke, but we were talking about making music together, and he goes, 'I'm gonna make you the biggest pop star in the world.'
"And we just laughed."
Meanwhile, Billie - who has earned her first ever Grammy nominations as well as performing at an awards show for the first time when she took to the stage at the American Music Awards (AMAs) last month previously said she can't believe how lucky she is.
She said: "I feel like I'm living someone else's life. For real. Man, I don't even, like, I don't even know. The things I get to do are so beyond anything that I ever thought I would even be close to.
"Honestly, I can't tell you how much I'm enjoying it. I'm enjoying myself and grateful for it, and have just been happy in it. Which is good for me and new for me to be happy."