This paper advances the concept of path‐prolonging critical junctures, a category used for eventful historical episodes marked by high levels of contingency that lock in path maintenance. It contributes to recent debates in comparative‐historical social science, adding a pathway of continuity that is the product of agency and activism. The analysis is grounded in the 1985 interruption of Chile's long‐standing state milk programme and argues that against a backdrop of economic, social and policy turmoil, expert and grassroots efforts combined to pressure the military regime to reverse retrenchment. The implications of this juncture help explain Chile's favourable infant malnutrition and mortality indices and the maintenance of a state‐run infant‐maternal primary healthcare network despite neoliberal reform.