Finland is officially a bilingual country but it is in practice multilingual. In the current study, we examined how mothers and fathers of mixed-language families linguistically identified themselves and others, and how ideological discourses and concepts historically and socially situated in Finland circulated through the parents’ talk. The parents of three families in which at least Finnish, Swedish and English were used on a daily basis were interviewed. A discourse nexus approach showed that the concept of ‘mother tongue(s)’ played a central role and that although all family members were in practice multilingual, there was a strong tendency across the couples to identify themselves and others as monolingual. Bilingualism was identified with Finnish-Swedish rather than other languages and a native discourse expressed bilingual identity as granted by birth rather than acquired later. The discourses could be traced back to official language registration procedures, the educational system in Finland, as well as to parents’ own lived experiences. The study illustrates the intricate relationships between language ideologies and how linguistic identities are created and performed among parents, and it pinpoints the need for further studies on how linguistic identities are passed on to and experienced by children along their life trajectories.