The vertebrate left-right axis is established during embryonic development by a ciliated organ called the left-right organiser. In zebrafish, this organ is known as Kupffer's vesicle (KV). A new paper in Development demonstrates that mitotic events taking place in the KV at an early stage of its development play important roles in shaping KV architecture and function. To learn more about the story behind the paper, we caught up with first authors Yan Wu and Yiling Lan, and the corresponding author Heidi Hehnly, an Associate Professor and Associate Director of the BioInspired Institute at Syracuse University, USA.