This study explores the role of parental ideologies in heritage language (HL) maintenance among three interlingual families in New Zealand. This study draws on data from semi-structured interviews with Korean immigrant mothers and non-Korean fathers. A thematic approach was used to analyze the data. The findings in this study revealed that the three families placed great value in Korean HL maintenance. All three family language policies (FLPs) centered around a "One Person, One Language" approach, with the mothers using Korean. However, there were still wide-ranging variations in their FLPs. Moreover, the mothers' attitudes toward HL learning were related to their perceptions of their children's identities, which affected their HL-teaching strategies. The mothers' HL maintenance efforts were possible because of their partners' support. However, their husbands' positive attitudes were also clearly associated with heteronormative gender roles and a related ideology of parenting. The findings suggest that even in positive FLP contexts, there is thus still a role for a more holistic and critical approach to HL maintenance.