With notable exceptions (such as the work of Li Wei, 1994, and Zentella, 1997), the majority of work on interaction within bilingual families has concentrated on the early years of language acquisition, with studies of later childhood and adolescence focussing mainly on school and peer group contexts. The present study addresses this gap by studying family interaction with children in late childhood/ adolescence, arguably a critical period in terms of the negotiation of linguistic identities. It draws on video recorded data from a longitudinal case study of a Spanish-English bilingual family, resident predominantly in Mexico, comprising Mexican-born mother, British-born father and twin boys. The data on which this presentation is based includes detailed analysis of naturalistic interaction at the point when the twins are aged 14, plus retrospective commentaries by the participants. It is supported by questionnaire, interview and recorded data drawn from a wider range of families with adolescent children. A key finding to emerge from the research has been the significance of gender in both the changing language preferences and the conversational code-switching strategies practised by the adolescents in the home context. Rather than attributing these solely to factors beyond the home, such as a generational shift in social networks or the status of particular linguistic codes in the surrounding community, there is evidence here for interpreting them additionally in terms of the performance of gender identities and the negotiation of power relations within the family. In the case study family, where each language has been predominantly associated with one parent, sibling rivalry for parental favour has frequently entailed displaying a strategic alignment with the maternal or paternal language, in order to ensure the most favourable outcome from an interaction. Additionally, at this stage in their lives, it is important for the boys to define themselves as distinct from their parents, and in particular their mother. The symbolic meaning attached to each language in this specific context may not extend to other contexts beyond the family. Code switching in the New York Puerto Rican, or 'nuyorican', community has been described by Zentella (1997, p.113) as 'a conversational activity via which speakers negotiate meaning with each other, like salsa dancers responding smoothly to each other's intricate steps and turns'. In the present study, by contrast, the family interaction more closely resembles the intricate moves of a fencing match, in which maternal and paternal linguistic codes are selectively deployed by the adolescents to attack and parry (or occasionally offer submission to) what are perceived as the maternal and paternal values.

References
- Li Wei (1994) 'Three Generations, Two Languages, One Family', Clevedon (Avon) and Philadelphia, Multilingual Matters Ltd.
- Zentella, A.C. (1997) 'Growing Up Bilingual', Oxford and Malden (MA), Blackwell Publishers