Abstract As children’s agency in influencing institutional language practices is often not carefully reflected in early childhood education curricula, the objective of this paper is to offer meaningful insights about how institutional language policies are both reproduced and transformed by children’s everyday use of language. For this purpose, we will combine conceptual resources from social theory, sociolinguistics and childhood studies in order to analyse children’s linguistic behaviour by applying a structure-agency perspective as a relational approach. Drawing on data from ethnographic field research within institutional day care centres in Luxembourg, our findings demonstrate that the status of children as actors in institutional language practices is strongly connected to institutional policies as a structural condition. However, this does not mean that children just enact these language policies, because they are actors of both maintaining, undermining and alternating them. In this respect, especially the translanguaging of children and caregivers plays a crucial role in the Luxembourgish context as it allows to build a bridge between the official institutional language policy and the individual linguistic repertoires. Considering the goal of establishing a plurilingual environment in early childhood education which now is paramount to the educational language policy of the Luxembourgish government, this article suggests that translanguaging practices should be considered as one of the key starting points to create a plurilingual ecology in and through everyday practice in the day care centres.