This paper focuses on identity construction in family discourse, with the objective to investigate how identities of an adult daughter (the older sister/adult child at home) are made salient in and through family talk. Guided by Harvey Sacks's (1995) work on membership categorization combined with sequential analysis (Stokoe, 2012), the study examines 15 h of audio-recorded conversations between a mother and her two children in a Chinese-Australian family. Two specific identities of the adult daughter – a home educator and a child – are discussed in this paper where the findings reveal that such identities are invoked and negotiated by participants via their self- and other-categorization. The adult daughter's self-positioning becomes visible in interaction through her turn design and category-implicative social actions, which orient to a set of category-packaged rights, responsibilities, and attributes that index a particular category. However, the invoked memberships are not only accepted but also challenged by other family members in following turns, which reflects how the adult daughter is positioned by them during different family activities. By exploring an adult daughter's membership categorization in family talk, this study contributes to the under-researched topic of identity construction in Chinese-Australian/Chinese family discourse.