In this study, the relationship between the family language practice and the level of linguistic (in)security of adolescent Gagauz speakers is examined in the context of an endangered language. To this end, a language-use questionnaire and linguistic insecurity scale were administered to 674 participants. The questionnaire included questions exploring demographic information, self-reported language skills, language acquired at home, parents' speaking proficiency and the language of interaction. The linguistic insecurity scale comprised (self)-evaluations of language practices, linguistic status and linguistic quality. Using a quantitative methodology, ten interviews were conducted. The findings show that the participants felt more secure while using Russian and there was a strong correlation between family language practice and linguistic insecurity perceived by the adolescent speakers. Moreover, language choice in interactions was found to be speaker-specific. In other words, as a part of the family language policy, the participants spoke Gagauz with their parents, siblings and grandparents. In some cases, however, the language choice was based on the ethnicity of the interlocutor and the language which friends and neighbours were speaking. It was found that although speakers felt secure and motivated to speak the Gagauz language, the use of Gagauz seemed to be limited to family contexts.