First-generation refugee children often experience pre- and post-migration adversity and display high levels of mental health/wellbeing difficulties, but to date, research has not examined the impact of such factors on refugee children's L2 acquisition. Accordingly, this study examined the influence of externalizing and internalizing problem behaviours (wellbeing), time in refugee camps and low socioeconomic status (SES) (adversity) on the English-L2 abilities of 117 Syrian refugee children (7–14 years) in their third year of residency in Canada. Wellbeing difficulties and adversity factors accounted for variance on L2 vocabulary, morphosyntax, listening comprehension and narrative production tasks, beyond the variance accounted for by age of L2 acquisition and length of L2 exposure. Specifically, externalizing problem behaviours, time in refugee camp, maternal education and maternal employment predicted variance in L2 abilities. It is concluded that refugee children could have influences on their L2 acquisition that are different from those of bilinguals with other backgrounds.

Previous research has established that early second language (L2) learners in classroom immersion may not ultimately produce all L2 morphosyntactic features as first language (L1) speakers of the language do, whereas L2 comprehension outcomes are reported to be less divergent from those of L1 speakers. However, immersion learners’ L2 comprehension is typically assessed using tasks of holistic understanding, and therefore, little is known about fine-grained comprehension of specific morphosyntactic constructions. To address this, the present study examined online comprehension of English plural–singular marking by Mandarin-speaking, English-immersion learners in Taiwan. This semantically transparent feature differs from the L1 grammar and is a notable area of difficulty for Mandarin-speaking L2-English learners. The present study assesses middle school-aged immersion learners’ comprehension using a visual-world eye-tracking task combined with a picture decision task, comparing results to age-matched English-monolingual controls. After more than 8 years of L2 exposure, the immersion participants showed similarities and differences to monolinguals in plural–singular marking comprehension as measured by eye-tracking, and were less accurate in their interpretations on the picture decision task. This study shows that comprehension differences for a semantically transparent morphosyntactic construction can be apparent even after many years for learners who started immersion at an early age.

Previous research suggests that increased second language (L2) input at home may not support L2 acquisition in children from migrant backgrounds. In drawing this conclusion, existing work has largely aggregated across family members. This study contrasts the effect of L2 input from older siblings with that from mothers. Participants were 113 child L2 learners of English (mean age = 5;10 [range 4;10–7;2]; mean exposure to L2 in school = 16.7 months [range 2–48 months]). All children had at least one older sibling. Using hierarchical linear regression modelling with controls for age, non-verbal reasoning and phonological short-term memory, we found that greater L2 input from siblings – but not mothers – was associated with stronger L2 abilities in narrative macrostructure, inflectional morphology, and vocabulary. Increased cumulative exposure to the L2 at school and greater maternal L2 fluency were also positively related to children's L2 inflectional morphology and vocabulary scores.

Recent research has focused on bilingual children’s performance on non-word repetition (NWR) and sentence repetition (SR) tasks, but it remains unclear how their scores can be expected to vary as a function of language exposure, which creates challenges for developing age-appropriate performance expectations. With the goal of examining the impact of limited language exposure on these tasks, French NWR and SR performance from 33 first graders (mean age 6 years, 10 months) in early total French immersion in English-speaking Canada was compared to prior work on bilinguals acquiring French in France. With a mean length of exposure of 1 year, 7 months, but a mean cumulative length of exposure of only 3 months, the children in immersion have much less daily exposure to French than the bilinguals in France. The results showed that children in immersion patterned with the other bilinguals for NWR, but had much weaker SR performance. Within-subjects analyses revealed that, for SR, the children in immersion had stronger scores on wh-questions and relative clauses, which suggests that these structures may be less sensitive to language exposure.

This study investigates the acquisition of grammatical gender in French by German L1 children (age of onset of acquisition (AO) 2;8-4,0). The analysis of spontaneous production data of 24 children gathered longitudinally and a gender assignment test administered to 8 of these children at ages 6;7-8;3 and to 9 children (AO 2,11-3;8) at ages 3;2-5;1 revealed that some of them resembled L1 learners whereas others behaved like adult L2 learners. The turning point is at around AO 3;6. AO is thus a crucial factor determining successive language acquisition.