This article examines the evolution of the understanding of child mental health based on documents that guide nursing practise in Brazil. Eleven relevant documents were submitted to normative analysis, which revealed four themes: Developmental approach of the child mental health; Brazilian policies and social history of children; Spaces for prevention, promotion, and care in children's mental health; and The (in)visibility of nurses' work in the context of mental health. These are linked through ideological and social constructions that have although transformed through the years yet remained the same in their core. Based on our results, we propose adopting a decolonial perspective to compose nursing knowledge to improve child mental health in Brazil.