Public service interpreters assume a key role in rendering accessible social services to newcomer clients. They could even be considered inherent to social work settings that are multilingual in nature, such as the interactional context of unaccompanied minors and their legal guardians. However, despite the intrinsic linguistic diversity and the unique position of interpreters in this setting, guardian–minor encounters remain unexplored in research. The current study therefore aims to provide insight into the multilingual needs and challenges in these encounters, focussing particularly on the roles interpreters play in this setting and how they are perceived to affect the interaction. To this end, the study draws on twelve semi-structured interviews with guardians of unaccompanied minors, collected as part of a research project examining the impact of multilingual strategies on the communication and relationship between guardians and minors in Belgium. Through thematic analysis, the study explores guardians’ insecurities, revealing confusion about the professional status of interpreters, concerns about interpretation quality and conflicting expectations of what interpreters should (not) do. The study provides recommendations with a view to improving both the confidence of guardians and the efficiency of guardian–minor interactions, and highlights the relevance of the findings for various other social work settings.