Adele revealed that the pair has been making late-night calls to various musicians, including Sam Sparro, pretending to be eight-year-old boys.
She told The Sun, 'Lily can't ever keep quiet and tells everyone it's me who leads her on to do them. It's not me it's her, she is so naughty.
'We have called Sam Sparro and pranked him. It was late and I was drunk. I don't remember a lot of it. Lily does a very good impersonation of an eight-year-old boy. Mine isn't so good.
'People get concerned when a child is on the phone but they soon realise it's a joke, usually because we both keep giggling.'