This paper investigates the relationship between a child's degree of
bilingualism and features of parental input. It seeks to demonstrate that
parental discourse strategies have a direct bearing on the levels of mixing
present in the child's utterances in his weaker language, English. It is
based on the longitudinal study of a Catalan/English bilingual child
from 1;3 to 4;2 years old. The strategies adopted by both parents in
response to their child's mixing are examined following Lanza's (1992,
1997) categorization of parental discourse strategies. Whereas the
Catalan-speaking mother negotiates a bilingual context of interaction
with her son, as of the child's third year, the English-speaking father
endeavours to impose a monolingual context. Such a change of strategy
clearly favours the child's increasing use of the minority language, which
entails a sharp decline in rates of mixing. It appears that parents'
pragmatic choices may have an impact on the development of productive
family bilingualism.