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Post written by François Grosjean.
Lauren is a little Dutch-English bilingual girl whom Belgian psycholinguist Annick De Houwer tells us about in one of her recent publications. Her father spoke English to her and her mother Dutch. But because her father worked hard, and saw her rarely—mainly on weekends—Lauren only heard English about three hours a week. When she was 3 years old, she could only say "yes" and "no" and this upset her father no end. He thought she was rejecting him.
Situations such as this one can be avoided in part if parents take the time to consider a number of questions when bringing up their child bilingual such as when should the languages be acquired, which bilingual strategy should be used, will the child have a real need for each language, what support can parents count on, etc. (see here). A question of primary importance concerns the type and amount of language input the child will receive, mainly from his/her parents but also from other sources.
Annick De Houwer has spent many years researching this precise point. Using a questionnaire approach, she examined the language behavior of close to 2,000 families in Dutch-speaking Flanders, Belgium, where at least one parent spoke a language other than Dutch in the home. The first thing she found was that despite the presence of both Dutch and another language in the lives of these families, nearly one-quarter of the families had no children who spoke the other language. This only confirms that factors such as those mentioned above are crucial when fostering a child's bilingualism.
But what is perhaps even more interesting is that different parental input patterns had different effects on whether the children became bilingual or not. For example, when both parents only used the other language in the home, its transmission rate was quasi perfect (97%). The success rate only decreased by three percentage points when one of the two parents also spoke Dutch in the home. As for the "one person, one language" strategy, and contrary to general belief, it only produced a 74% success rate. In other words, a quarter of the children to whom the father spoke one language and the mother the other, simply did not become bilingual. It is interesting to note that both parents speaking both languages to their children obtained a score that is not significantly different (79%). As for the situation where one parent spoke both Dutch and the other language, and the other parent only spoke Dutch, then only 36% of the children spoke the other language.
Studies are still trying to isolate the reasons that underlie results such as these but what seems clear is that when the minority language is used exclusively, or at least extensively, in the home, it will be acquired by the child. Not only is there more parental input of that language but the home environment is conducive to using it. Thus there is every chance that the child will grow up speaking it. As for the majority language, it will be picked up very quickly, but mainly outside the home.
To better understand what is taking place in bilingual homes, researchers are turning more and more towards large databases of natural conversations in bilingual families. One of these was obtained by Canadian psycholinguist Shanley Allen in five families who, at home, speak both English and Inuktitut, one of the main Inuit languages in Canada. Annick de Houwer used it to examine the amount of dual language input the children received and the outcome of this on their bilingual language production. What she found was that caregivers who spoke more English had children who also spoke more English and, conversely, those who spoke more Inuktitut had children who used that language more. This simply substantiates the fact that the length of time a language is heard and used is a crucial factor in its acquisition by children.
In another study, Annick De Houwer examined trilingual families in Flanders. They used two minority languages in the home and some also used Dutch whereas others did not. In the latter case, Dutch was picked up outside the home, primarily at school. Once again, she found that despite this trilingual input, not all children actually spoke the three languages—two-fifths were trilingual, more than a third were bilingual and more than a fifth spoke only one language. Thus trilingual input is no guarantee to actually developing three languages.
Two factors played an important role in accounting for these results. The first is that when no Dutch was spoken in the family, and only the two minority languages were used, then the probability of becoming trilingual was higher. Three-quarters of the families in that case had children who were actively trilingual. The other factor was that when both parents (and not just one parent) used both minority languages with their children, then the chance of having trilingual children was higher.
In sum, children being brought up with two or more languages will need as much language input as they can from each of their languages, but primarily the minority language(s). The majority language is in less danger and will get its input in varying ways, outside and inside the home.
To end, let's go back to the example given at the beginning of this post. Little Lauren's lack of English was not a sign that she was rejecting her father. She simply had not received enough English input from him in the very restricted amount of time she spent interacting with him in their common language!
Visit François Grosjean's website here.
References
De Houwer, Annick (2007). Parental language input patterns and children's bilingual use. Applied Psycholinguistics, 28, 411-424.
De Houwer, Annick (2009). Bilingual First Language Acquisition. Bristol: Multilingual Matters.
Allen, Shanley (2007). The future of Inuktitut in the face of majority languages: Bilingualism or language shift? Applied Psycholinguistics, 28 (3), 515–536.
