SIMULTANEOUS BILINGUAL ACQUISITION

As mentioned earlier, much of the research on children acquiring two or more languages from birth has been conducted by linguists studying the language development of their own children. Studying one’s own children has many practical advantages. Living with the children in the same household, parents can observe children’s language development unobtrusively as participant observers. They have the advantage of interacting with the children throughout the day (e.g., during play time, meal time) and night (e.g., during bedtime, bath time)—few outside researchers have regular access to such intimate family settings. They also have privileged access to their participants for a long period of time—it is possible to follow the development of the same children for ten years or more. Parent researchers can keep language diaries and make audio/ video recordings to document children’s authentic language use in various settings with different people. Information on family background and circumstances, as well as the language histories of each child can also be provided in detail.

The earliest systematic studies of simultaneous acquisition of two languages were carried out by Jules Ronjat (1913) and Werner Leopold (1939-49), who raised their children bilingually. Ronjat introduced the OPOL principle as the most effective method for raising a child bilingually in a home where the parents speak different mother tongues. The OPOL strategy was also used by Leopold who studied his daughter Hildegard’s acquisition of English and German in the U.S. Leopold spoke only German to his wife and Hildegard, while his wife spoke only English. Leopold claims that Hildegard initially did not separate the two languages and did not associate the languages with specific persons even though he and his wife spoke to her in different languages. He states that it was only in her third year that Hildegard began to treat the two languages as separate linguistic systems and was able to translate between them.

Leopold’s observation led to subsequent claims that simultaneous bilingual children start out with a single linguistic system. Perhaps most influential in this regard, Volterra & Taeschner (1978) argued that a child exposed to two languages becomes bilingual in three stages: (1) the child has one lexical system which includes words from both languages; (2) the child distinguishes two different lexical systems but applies the same grammatical rules to both languages; (3) the child has two language systems, differentiated both in lexicon and in grammar, but each language is exclusively associated with the person using that language. Volterra & Taeschner’s argument for the existence of an initially fused system was based on the speech of two German-Italian bilingual children whose words (at ages 22 months and 18 months respectively) had no translation equivalents (i.e., words used in one language that correspond to words with the same meaning in the other language).

However, this model has attracted significant criticisms, and there is now a consensus in the field of child bilingualism that a child’s two languages develop separately from the very beginnings of speech production (see De Houwer, 2009; Deuchar & Quay, 1998; Meisel, 2006). Several studies have shown that bilingual children use the two grammars differently as soon as there is evidence of grammar (Dopke, 1997; Paradis & Genesee, 1996; Yip & Matthews, 2007). Furthermore, the claim that bilingual children start out with a single, undifferentiated vocabulary is challenged by research that shows that bilingual children develop a fairly stable rate of translation equivalents as soon as they begin talking (Pearson, Fernandez, & Oller, 1995; Quay, 1995).

When compared to monolingual first language acquisition, simultaneous acquisition of two languages proceeds through the same developmental phases as those observed in the respective monolingual children (Meisel, 2006). Both monolingual children and bilingual children start off their conventionally meaningful language production using single words, then go on to produce two word combinations and multi-word sentences before they produce complex sentences (De Houwer, 2009). Bilingual children’s overall rate of acquisition in each of these languages is also comparable to that of mono- linguals—there is no evidence that simultaneous bilingual children develop morphosyntax faster or slower than monolingual children (De Houwer, 2009; Meisel, 2006).

Overall, simultaneous bilingual children’s development in each language is qualitatively no different from monolingual children’s development in those languages, and leads to the same kind of grammatical competence possessed by monolinguals. This does not mean, however, that a bilingual child is “two monolinguals in one person” (Grosjean, 2010). Rather, bilingual children

acquire competence and skills in each of their languages according to their specific communicative needs and preferences.