In research on language choice patterns in bilingual families, most of the study cases are based on reports written by linguists about their own children language development. Therefore, there is a strong possibility that the parents’ scientific and theoretical knowledge as linguists might have influenced in the child’s bilingual acquisition. To overcome this approach limits, the methodology of Conversation Analysis was applied to two study cases based on empirical data, which were carried out on two (Brazilian) Portuguese-English bilingual families to determine how language strategies are applied in real-life conversations. The interactions within the members of two families were analyzed to test the effectiveness of the language strategies. The extensive set of data collected in this study shows that none of the families strictly applies the policies. The effectiveness of such practice is therefore to be questioned.