This article approaches newcomer migrant girls' experiences with social competition and relational aggression. This the authors do through a detailed analysis of the interactional practices that a group of preschool-aged girls make use of as they socially exclude one of two newcomer migrant girls from participating in a sharing activity involving self-made artefacts. The data is drawn from ethnography combined with video recordings of natural and situated activities of the girls' interactions in a Norwegian day-care institution over the course of nine months. Combining structural and social-constructivist perspectives, the authors discuss how a day-care group is a social field comprising multiple subfields characterized by agents struggling over position and power. Overall, this article addresses another side of the generally accepted positive view of day care for migrant children, revealing how relational aggression might be embedded within seemingly harmless activities and set in everyday child-governed activities. Finally, the authors reflect on implications for pedagogical practices and make suggestions for future research.