Bilingual first children’s language acquisition

Bilingual first children, also often referred to as 2L1 children or simultaneous bilingual learners, are a very special group of bilingual learners. They are introduced to two or more languages from birth and have the advantage of a very low AoA and long exposure to L2 (the society’s language), two factors that positively impact their language skills. The comparison of this group of bilingual learners’ long-term L2 development to that of monolingual learners is of special interest since such group comparisons provide a good design for disentangling possible “deficits” in bilingual learners’ language learning from other mechanisms influencing language development, such as AoA (De Houwer, 2009a). However, not even for this group of children do researchers agree upon whether they have language levels comparable to those of their monolingual peers.

De Houwer claims that 2L1 children develop language skills equal to those of monolingual learners and that they reach language milestones at the same pace as their monolingual peers (De Houwer, 2009a, 2009b, 2012). She goes so far as to say that if they do not reach these milestones at the same ages as their monolingual peers, there is a need for language evaluation to ensure that they do not have a language disorder (De Houwer, 2018). The studies she builds her case on, claiming bilingual first children exhibit language levels equal to those of monolingual learners, could, however, be more solid. The book “An introduction to

bilingual development” (De Houwer, 2009b) is criticized for not including any longitudinal studies (Ringblom, 2010). A search through the rest of her references in the articles/books cited above shows that many of the studies with which De Houwer supports her claim are of bilingual first learners only, combined with comparisons of literature describing the ages of language milestones for monolingual learners. The characteristics of the studies referenced that do compare a 2L1 sample to an actual monolingual sample are presented in Table 2 in appendix 2.

The majority of these studies focus on toddler age. With the exception of case studies, longitudinal studies are scarce (3 studies of toddlers), as are studies with participants aged 5 years or older (4 studies where the oldest sample is 8-year-olds). The studies of children 5 years or older either compare the 2L1 children’s L2 levels to the norms of monolingual learners or have small sample sizes (N = 30, N = 36). Small sample size and/or comparisons with norms are general problems with most of the cited studies. The larger studies that she cites, such as Umbel, Pearson, Fernández, and Oller (1992) and Barrena, Ezeizabarrena, and Garcia (2008), compare the 2L1 children’s language skills to the norms of monolingual learners. The study of Barrena et al. (2008) is, however, interesting. They find that bilingual first learners 16-30 months old exposed to L2 more than 60% of the time obtain language levels comparable to monolingual norms. Less exposure to L2 was associated with lower language levels.

Although De Houwer argues for equal language levels between 2L1 children and monolingual learners, other researchers disagree

(Bialystok & Feng, 2011; Grant, Gottardo, & Geva, 2011; Hoff et al., 2018). Hoff et al. (2018) compare the language levels of what seems to be a combined cohort of 139 early bilingual learners/bilingual first learners with 39 monolingual children. Hoff et al. (2018) find that bilingual children at 5 years of age were lagging behind their

monolingual peers by 6 months to a year in English, depending on the amount of parental exposure to English. Note, however, that even

though the researchers report that the bilingual learners were exposed to both languages by infancy (30 months), they also state that some of the children lived in homes where Spanish was spoken exclusively. It is therefore difficult to determine what percentage of the bilingual

learners were truly bilingual first learners. The lack of comparable language levels in this study could therefore be caused by the inclusion of bilingual children with an onset of L2 later than birth. Bialystok and Feng (2011) study a group that contained purely bilingual first

learners. Bialystok and Feng (2011), however, do not divide bilingual first children into groups based on their amount of L1/L2 exposure.

The bilingual children are all treated as one sample. The researchers investigate the effect size difference in language levels across all children in the age span of 5-9 years of age. Their large cross-sectional study consists of 963 participants in the age group of 5- to 9-year-olds, of whom half were monolingual learners and the rest were bilingual learners with an AoA from birth. The effect size difference in language skills in the majority language was large across all age groups and favoured the monolingual learners. Furthermore, a reanalysis of data from Pearson, Fernandez, and Oller (1993) performed by Bialystok and Feng (2011) shows the same pattern. (This study is one of the

references cited by De Houwer in her 2009 books claiming equal levels in the instructional language.) Bialystok and Feng (2011) therefore claim that the patterns of lower vocabulary skills hold true for the productive vocabulary of children in the first two years of life as well as receptive vocabulary in preschool and early school years (Bialystok

& Feng, 2011). Since large-scale studies have the advantage of increased statistical power (Ingre, 2013), the large-scale study of Bialystok and Feng (2011) is likely a more solid proof than De Houwer (De Houwer, 2009a, 2009b, 2012, 2018). It is, however, worth

mentioning that none of these studies base their conclusions on large scale longitudinal data.