Billie Eilish's rise and success has had a lot to do with the chemistry between her and her elder brother Finneas O'Connell. As her producer and songwriting partner, the two have generated three years of releases that have seen her become one of the biggest names in music. As FINNEAS, he has also been releasing his own music for the same length of time. Hear Richard Kingsmill explore how he got started, how he writes and works with Billie as well as his latest songs.