Input and Caretaker Proficiency in Early Bilingual Development: Mothers, Helpers and Toddlers

Project: Research

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The quality of language input has a massive impact on the child’s language development. In Hong Kong, many young children develop knowledge in English through daily interaction with their caretakers such as mothers and Filipino domestic helpers, who speak Cantonese or Tagalog as their first language (L1) and vary in their proficiency in English, their second language (L2). Existing research shows that caretakers with ‘good’ proficiency in the L2 can provide high-quality language input for young children in that language. However, the evidence has mainly come from Spanish immigrant families in the US, using composite and indirect proficiency measures. Little do we know about the input provided by caretakers whose L1s are typologically and culturally distant from English or those in multilingual contexts like Hong Kong.To fill these gaps, this study builds on the PI’s existing projects and investigates two sources of English input directed to Cantonese-English bilingual toddlers in Hong Kong: Cantonese-L1 mothers and Tagalog-L1 helpers, with English-L1 mothers as controls. In addition to general input measures such as lexical diversity and grammatical complexity, we will closely examine the verb lexicon and tense/agreement morphology in the caretakers and the children. Research has shown that verb morphology causes persistent difficulty for both adult and child Chinese-L1 learners of L2 English. With Cantonese instantiating little inflectional morphology and Tagalog rich and complex verb morphology, it is likely that these L1 characteristics will be carried over to child-directed speech and impact on the child’s development in English differently. Adopting a Time 1/Time 2 design, this study will measure caretakers’ proficiency and input quality directly and accurately through standardized tools and caretaker-child interaction tasks at child age 2.5 years (Time 1), and assess child developmental outcomes in English and Cantonese through a battery of language and cognitive tests at age 3 (Time 2).This study will advance the frontiers of bilingual acquisition research by identifying fine-grained qualitative features of language input provided by L2 caretakers with different L1s and evaluating to what extent these features are predicted by the caretakers’ proficiency and will predict the children’s developmental outcomes at age 3 with unprecedented accuracy and precision. The findings will enable parents to reach scientifically informed decisions on whether, who and how to talk to their children in a non-native language, and have important policy implications on home-based input planning and intervention in Hong Kong, mainland China and beyond. 


Project number9048256
Grant typeECS
StatusNot started
Effective start/end date1/01/23 → …