This song originally came to vocalist Ben Romans-Hopcraft in a dream when it was performed by an incarnation of American rock band Smith Westerns. He recalled to NME: "I thought, 'These melodies are crazy.' I woke up and realized it was actually my melody because it was my dream."
"There's a video on my laptop of me recording it half-asleep in my pants that I found a couple of weeks later."
Lacuna is largely based on memories of Brixton, where Childhood co-founders Ben Romans-Hopcraft and Leo Dobsen both grew up. This song is a biting critique of the South London district. "Most of the record is about growing up in South London," Romans-Hopcraft told NME. "It's about me thinking that everything's dandy [here], but [realising] it's actually not and coming to terms with that."
