Lying on my son’s bed as he fell asleep, I couldn’t believe quite how much the glow-in-the-dark star stickers on his ceiling resembled the real thing. Even so close, they evade your focus as a real star does from inconceivable distance. As the fovea dances around them and the eye’s blind spot flicks across the imaginary sky, they even seem to twinkle. At the edge, where the landing light spilled through the crack between door and doorframe, there was the last hint of sunset. He snorted, fidgeted, turned around to me and asked: ‘Daddy, what happens if you have a boiled egg?’ I gazed into the infinite blackness between the stars and answered him as best I could, and we drifted together, reassured.