In 2018, the Italian Coast Guard rescued 190 migrants onboard an overcrowded vessel from Libya. Held at sea for five days, the Italian government finally permitted the Coast Guard to dock in Catania, Sicily, yet refused to allow the migrants to disembark. This article begins by dissecting the anatomy of this crisis, tracing the diverse actors and institutions involved in its creation and resolution through first-hand accounts. Multi-sited ethnographic research reveals how a diverse set of actors enlisted a hierarchy of vulnerability to secure the release of migrants onboard, privileging unaccompanied asylumseeking children in particular. The article examines how this hierarchy has proven effective in legislating specialised protections and services and accessing limited humanitarian aid. However, a hierarchy of vulnerability has two paradoxical yet mutually reinforcing consequences. First, focusing on the vulnerabilities of increasingly narrow categories of individuals, such as unaccompanied children, distracts from examining how state policies produce vulnerability. Second, the humanitarian organisations' emphasis on vulnerability re-inscribes social boundaries, making state protections and services progressively difficult to access. In so doing, both the state and humanitarian organisations govern youth mobility through vulnerability.