Songbird was written in half an hour at 3am when she couldn’t sleep. She says: "Fortunately, I had a piano in my room [but] nothing to record it on, but I had to play this song. The whole song [came out] complete: chords, words, everything within half an hour. I couldn’t go to sleep in case I forgot it, so I had to play it all night long."
RIP Christine McVie. It was worth playing all night long.