<p>This dissertation is composed of a quantitative investigation of Incomplete Heritage Language Acquisition and Attrition in heritage speakers’ vocabulary knowledge. This portion is followed by a qualitative investigation of Heritage Language Acquisition and Maintenance in which the immigrant parents’ attitudes towards heritage language acquisition and maintenance for their children are explored. Three groups of participants took part in this study. One group consisted of thirty 6-18 year old Persian-English simultaneous and sequential bilinguals in New Zealand. To obtain benchmark data, a control group was recruited, comprised of thirty monolingual speakers of Persian in Iran who were matched with the heritage speakers in terms of age, gender, number of siblings and their family’s socio-economic status. The third group of the participants consisted of twenty-four parents of the heritage speakers. Information about the bilinguals’ demographic and socio-linguistic factors was collected through semi-structured interviews with their parents. The quantitative investigation commences with a study that examines young heritage speakers’, either simultaneous or sequential bilinguals, vocabulary knowledge in their family language compared to the matched monolingual counterparts, and the factors that account for a difference, if there is any, are investigated. These factors include current age, age at emigration, length of emigration, frequency of heritage language use and parents’ attitude towards heritage language acquisition and maintenance. The results of productive and receptive vocabulary knowledge tests showed that the heritage speakers were outperformed by the monolinguals, but the gap was wider in the case of the simultaneous bilinguals. Additionally, the parents’ attitude was found to be a strong predictor of the simultaneous bilinguals’ vocabulary knowledge, while the sequential bilinguals’ vocabulary knowledge was associated mostly with age at emigration. The second study in the quantitative investigation examines whether the simultaneous and sequential bilinguals differ from monolinguals with regard to lexical richness, according to measures of lexical diversity and lexical sophistication, in their family language. It also weighs the influence of the demographic and/or sociolinguistic factors on the difference between these sub-groups, if there is any. A film-retelling task was used to collect free speech samples. As expected, the monolinguals’ narratives tended to manifest greater lexical richness according to both measures, but did most markedly so according to the lexical sophistication measure, suggesting that the latter is a better parameter in detecting the differences between heritage speakers and monolinguals. Of the factors investigated, the simultaneous and sequential bilinguals’ lexical richness was predicted by age, showing that the older the children were when they moved to the second language environment, the better their family language vocabulary tended to be. The sociolinguistic variables (i.e. Persian use and parental attitude) were not found to play a significant role in the results of the two quantitative studies. This might have been due to the fact that the demographic variables (i.e. age and age at emigration) were so strong that they overrode the influence of the sociolinguistic variables. Alternatively, the Likert-scale items used in the questionnaire-based interview may have been too blunt an instrument to discern subtle and yet relevant sociolinguistic differences among families. This raised a need to conduct a qualitative investigation in case a more in-depth analysis of the interview data might reveal a clearer picture of their influence. The qualitative portion of this dissertation begins with an exploration of the immigrant parents’ attitudes towards their children’s development and maintenance of their heritage language by utilizing Spolsky’s (2004) model of language policy as a methodological framework. The data consist of the same semi-structured interviews with twenty-four parents of the heritage speakers as used in the quantitative investigation. The findings reveal that although the parents hold positive beliefs about family language acquisition and maintenance, there are discrepancies between their language ideologies and family language practices and efforts. In light of these inconsistencies, this study suggests that analyses of parental language attitudes towards heritage language maintenance should not only consider their beliefs towards minority language acquisition and maintenance, but also their language practices and management. It was also found that the majority of Iranian parents in this study were satisfied if their children had good conversational skills in Persian. This finding led me to look into the parents’ attitudes towards their children’s acquisition and maintenance of Persian literacy. Following the first part of this investigation, the parents’ beliefs, practices and management strategies were explored to see how they reflect their attitudes towards their children’s heritage language literacy acquisition and maintenance. The findings revealed that it was very uncommon for the heritage speakers to have high literacy skills, which the parents attributed largely to the lack of community-based heritage language schools in the host country. Furthermore, parents’ efforts in heritage language literacy development and maintenance can be explained through the concept of investment (Norton, 2000). It seems that the parents choose not to promote investment in heritage language literacy, when they do not see it as a part of their children’s imagined identities. Additionally, while conversational fluency and cultural knowledge were continuously positioned as being extremely important for the heritage language speaking children by the parents, it was not seen as connected to traditional literacy. Investigating the different aspects of heritage speakers’ lexical knowledge, the quantitative portion of this dissertation furthers our understanding of incomplete acquisition and attrition of family languages in simultaneous and sequential bilinguals. Additionally, the qualitative portion illustrates that positive parental beliefs do not guarantee heritage language acquisition and maintenance. This investigation also raised immigrant parents’ awareness of the role literacy can also play in heritage language maintenance. Taken together, this dissertation draws the attention of researchers, educators, immigrant parents and communities to various social and linguistic aspects of young heritage speakers’ acquisition and maintenance of their family language as they grow up.</p>
