Eilish and her brother Finneas O'Connell collaborate on songwriting.[63][64] Eilish called Finneas her partner in making music.[63] He writes for her albums, produces her music and also performs with her on live shows.[65][63] Eilish and Finneas "like to completely make up things and become characters" and "have songs that are really fictional".[64] Eilish said a number of the songs also derive from her and Finneas' experiences.[64] They try to write "really interesting and conversational" lyric
When We All Fall Asleep, Where Do We Go? was released on March 29, 2019.[39] The album debuted at number one on the Billboard 200 as well as on the UK Albums Chart, making Eilish the first artist born in the 2000s to have a number one album in the United States, and the youngest female ever to have a number one album in the United Kingdom.[40][41] Upon the album's debut, Eilish broke the record for most simultaneously charting Hot 100 songs by a female artist, with 14, after every song from the