Mom always said you need your sleep, and it turns out, she was right. According to a new study, the lack of sleep in young fruit flies profoundly diminishes their ability to do one thing they do really, really well — make more flies. To address whether sleep loss in young flies affects development of courtship circuits, the team investigated a group of neurons implicated in courtship. One particular subset of those neurons was smaller in sleep-deprived animals than normal flies, suggesting a possible mechanism for how sleep deprivation can lead to altered courting behavior.