Billie Eilish has revealed which songs were most important to her growing up.The US singer-songwriter, 18, listed songs by Britney Spears, Avril Lavigne and The Beatles as essential to her childhood – particularly Lavigne’s ‘Losing Grip’.“This is my favourite Avril song ever, a very big song from my childhood as well as ‘Complicated’, as well as ‘I’m With You’, as well as ‘Sk8er Boi’, ‘Girlfriend’, blah, blah, blah, ‘Keep Holding On’, Eilish told me & dad radio on Apple Music.