Billie and Finneas grew up close together, given they were both homeschooled by their mother, Maggie, and even given songwriting lessons.
Speaking to Atwood magazine about his collaboration with his sister, Finneas, 22, said: “Being able to hear an artist and emulate them has been a huge part of being successful as a producer and co-writer…
“Well for Billie, if I’m writing a song alone for Billie like Ocean Eyes or Watch or Six Feet Under, I want to write a song that I think she’ll relate to and enjoy singing and empathise with the lyrics and make her own.
“And if I’m writing a song with Billie I’m just trying to help her tell whatever story she’s trying to tell, bounce ideas off of her, listen to her ideas.
source: express.co.uk