In recent years, there has been increased interest in the cerebellum by developmental neuroscientists [1], with a particular focus on the prenatal period 2, 3, 4, 5. Given its protracted development and enormous cell growth in late gestation [6], the prenatal cerebellum is particularly sensitive to perturbation from teratogenic influences [7]. This vulnerability has implicated the fetal cerebellum in a wide range of later-developmental outcomes, including sleep disruption [8] and child psychopathology [9]. In parallel to this recent work, we are now starting to understand how the developing cerebellum impacts later-behavioral outcomes through its unique transcriptomic landscape [10], and cellular and circuit-level disruptions incurred during gestation [11]. These novel findings suggest that to understand the unique functional role of the human cerebellum in cognition, we need to turn our attention to the smallest ‘little brains’.