This paper investigates how parents explain, frame and defend their particular family language policies. We focus here on 24 families who are attempting to achieve additive Spanish-English bilingualism for their children, an aim which in many cases requires parents to use and to teach a language that is not their first language, nor the primary language of the home or wider community. We explore how parents make these decisions; how parents position themselves relative to "expert" advice and other members of their extended families; and how these decisions are linked to their identities as "good" parents. Our data suggest that parents draw selectively from expert advice and popular literature, using it to bolster their decisions in some cases while rejecting it in others. Extended families, in contrast, generally were raised in the interview discourse as points of (negative) contrast. Overall, we find that parents primarily relied on their own personal experiences with language learning in making decisions for their children. Our data further suggest that family language policies for the promotion of additive bilingualism have become incorporated into mainstream parenting practices, but also that these parents' efforts could be better supported.