This article mobilises transdisciplinary inquiry to explore and deconstruct the often-used comparison of racialized/colonized people, intellectually disabled people and mad people as being like children. To be childlike is a metaphor that is used to denigrate, to classify as irrational and incompetent, to dismiss as not being knowledge-holders, to justify governance and action on others' behalf, to deem as being animistic, as undeveloped , underdeveloped or wrongly-developed, and, hence, to subjugate. We explore the political work done by the metaphorical appeal to childhood, and particularly the centrality of the metaphor of childhood to legitimising colonialism and white supremacy. The article attends to the ways in which this metaphor contributes to the shaping of the material and discursive realities of racialized and colonized others as well as those who have been psychiatrized and deemed 'intellectually disabled'. Further, we explore specific metaphors of child-colony, and child-mad-'crip'. We then detail the developmental logic underlying the historical and continued use of the metaphorics of childhood and explore how this makes possible an infantilisation of colonized peoples and the global South more widely. The material and discursive impact of this metaphor on children's lives, and particularly children who are racialized, colonized, and/or deemed mad or 'crip', is then considered. We argue that complex adult-child relations, sane-mad relations and Western-majority world relations within global psychiatry, are situated firmly within pejorative notions of what it means to be childlike , and reproduce multi-systemic forms of oppression that, ostensibly in their 'best interests', govern children and all those deemed childlike .