Many children, perhaps the majority of children in the world, are exposed to more than one language in early childhood. Children who hear more than one language virtually from birth are sometimes referred to as ‘simultaneous bilinguals’, whereas those who begin to learn a second language later are referred to as ‘sequential bilinguals’. There is a considerable body of research on the ability of young children to learn more than one language in their earliest years. The evidence suggests that, when simultaneous bilinguals are in contact with both languages in a variety of settings, there is every reason to expect that they will progress in their development of both languages at a rate and in a manner which are not different from those of monolingual children. Naturally, when children go on to have schooling in only of those languages, there may be considerable differences in the amount of metalinguistic knowledge they develop and in the type and extent of vocabulary they eventually acquire in the two languages. Nevertheless, there seems to be little support for the myth that learning more than one language in early childhood slows down the child’s linguistic or cognitive development.
There may be reason to be concerned, however, about situations where children are virtually cut off from their family language when they are ‘submerged’ in a second language for long periods in early schooling or day care. In such cases, children may bring to lose the family language before they have developed an age-appropriate mastery of the new language. This is referred to as subtractive bilingualism, and it can have serious negative consequences for children from minority groups. In some cases, children seem to continue to be caught between two languages: not having mastered the second language, they have not continued to develop the first. Unfortunately, the solution which educators often propose to parents is that they should stop speaking the family language at home and concentrate instead on speaking the majority language with their children. The evidence seems to suggest that the opposite would be more effective. That is, parents who themselves are the learners of the majority language should continue to use the second language which is most comfortable for them. The children may eventually prefer to answer in the majority language, but at least they will maintain their comprehension of their family language. This also permits the parents to express their knowledge and ideas in ways that are likely to be richer and more elaborate than they can manage in their second language.
There’s no evidence that a child’s brain has a limited capacity for languages such that their knowledge of one language must shrink if their knowledge of the other one grows. Most minority language children do eventually matter the majority language, but second language acquisition takes time. It may take several years for children to know the language well enough to use it for school learning with the same ease as children who have learned the language. Demographic research shows that minority languages are usually lost in the second generation after immigration. Children who have the opportunity to learn multiple languages from early childhood and to maintain them throughout their lives are fortunate indeed, and families that can offer this opportunity to their children should be encouraged to do so.