The role of metapragmatics in maintaining interactional coherence and achieving intersubjectivity has been variously underscored in the last three decades. In particular, raising metapragmatic awareness has become increasingly salient in research on intercultural communication and foreign/second language teaching. However, the topic has not been hitherto discussed in connection with heritage languages, and this is a gap that the present paper aims to fill. Based on interviews with Greek Melburnians who belong (in triads or dyads) to the same family but to different generations, a typology of metapragmatic awareness indicators encountered in the data is presented. Quantitative examination of one type of indicators—those oriented towards the addressee—indicates a decrease in their use across three generations. Similarly, examination of the variants of second-person pronouns and/or verb endings (the T/V distinction) brought to the fore alternations in the T and V forms, indicative of linguistic insecurity, as well as an increasing preference for the informal variants across three generations. The qualitative analysis of extracts from the interviews shed further light on the insecurity regarding the T/V distinction. Overall, the results point to changes in the communicative style of Greek Melburnians, namely away from positive politeness features (typical of the Greek society) towards English interactional norms, and the fostering of a hybrid communicative style—in alignment with their hybrid identities. It is suggested that politeness issues be integrated into the teaching of Greek as a heritage language.