A persistent myth about bilingual language development

Many pediatricians, speech and language therapists, child care professionals and preschool teachers are still convinced that bilingual children start speaking later than monolingual ones. This sounds plausible, because in a bilingual setting there is actually more to learn, is there not? And so wouldn't it be just normal that language development takes longer?
Fortunately, there is no supporting evidence for the assumption that bilingual children need more time for language development than monolingual ones. This article briefly summarizes the facts. These facts are backed by research results. The text furthermore explains how believing in a delayed bilingual language development can harm children and their families.

Variable pace of language development in all children

Children show great variability when it comes to language development in the first five years of life. While one child might be telling a short story at age two and a half, another child of the same age may still find it quite hard to form short sentences. Both examples are part of normal variation. There are three-year-olds who speak quite clearly so you can easily understand them, while other three-year-olds are only understood by people who know them – if you don't know them you can only guess at what they are trying to say, because they do not speak clearly. Again, these examples are within the range of normal variation.
The range of variation shown above applies both to children who have heard two languages from birth and to children who have heard only a single language from birth. In fact, when you compare bilingual and monolingual children, you finds that some children who are growing up bilingually develop their language skills at a faster rate than some children who are growing up monolingually. At the same time, you can find differences the other way around: some monolingual children develop their language skills faster than some bilingual children. However, there is no evidence for a general difference in language development based on the number of languages a child has heard from birth.

Milestones of early language development: minimal expectations

The fact that the pace of early language development varies greatly amongst all young children does not mean that it is not important at which age children master certain components of language use. There are, in fact, minimal skills which can be expected to be acquired by a certain age. These minimal skills are called milestones. If a child has not reached a specific milestone at the corresponding age, this might be indicative of a language learning problem. If this is the case, specialized staff such as speech and language therapists should assess the child in order to find the reason for the unexpected delay and design an intervention so the child's course of language development may be guided in the best possible way. Examples of milestones are:

(1) By the end of the second year, children can say a minimum of 50 different words.

(2) Around their second birthday children can combine two words into a single utterance.

(3) In the fourth year of life, children are able to form complex sentences containing main clauses and subordinate clauses.

You can find more information about milestones like these and on children's early development through the UK-based website of Speech and Language UK and the website of the National Institute on Deafness and Other Communication Disorders  (one of the National Institutes of Health) in the United States.

These websites focus on English but similar milestones exist for all languages. No matter if it is Chinese, Russian or German, one can expect that a four-year-old can explain quite well why she definitely needs that particular dress, and that a five-year-old is generally capable of telling quite elaborate (if somewhat boring) jokes.
Whether a child has heard one, two, or three languages since birth does not matter for these milestones. You can check out the scientific sources written by top specialists that we list below this article for more information.

Language development: a holistic approach

Regardless of whether they are raised bilingually or monolingually most children reach the major language development milestones at the expected age. When you are trying to assess a child's language skills it is important to consider their totality. Just as you wouldn't limit your assessment of a monolingual child based on what she or he says on Monday, Tuesday, and Wednesday, you should not limit the assessment of a bilingual child to one language only. Instead, studies and assessments should include all languages a child is learning. This is necessary to get a full picture of the child's language abilities. There is no language delay if a bilingual child has reached major milestones in at least one of her*his languages.

The myth of a delayed language development in bilingual children gets in the way of harmonious bilingual development.

If a pediatrician thinks that bilingual children generally develop language slower than their monolingual peers she will not be alarmed when a bilingual two-year-old who is brought to her practice does not speak yet. She will tell the worried parents that this was normal and that their child will just start to speak later. In our example, though, the child is still not speaking at age three.
This triggers further assessment, which shows that the child can hardly hear anything and that the supposed "delay" therefore has nothing to do with the bilingual environment. However, by then, family life has been burdened by the absence of well functioning parent-child communication. At the same time, the child has lost valuable time needed for the acquisition of vocabulary and grammar. Had the pediatrician been guided by evidence-based insights about early bilingual development instead of prejudice the child in this unfortunately all too realistic example could have received the help he needed much earlier, and would have had a much better prognosis for his language development. Prejudice can thus get in the way of harmonious bilingual development.
Undetected hearing problems at birth or hearing problems caused by, for example, multiple ear infections are amongst the most common causes for an unusual or delayed course of language development. If young children present with an unexpected course of language development, first and foremost their hearing should be checked, regardless of the number of languages used at home.

Conclusion

Bilingual children show the same large range of variability in language development as seen amongst monolingual children. It is paramount that they reach the language development milestones that are expected at a particular age in at least one of their languages. If there is a delay in language development or if a particular milestone has not been reached the underlying reason should not simply be attributed to a bilingual environment, but should be examined in the same way as with monolingual children. If a child has a language problem it will show up in all the languages a child is in contact with, not just in one of them. This is one more reason why it is so important to consider the totality of a child's languages in any language assessment.

Bibliography
Here you can find the references used as a basis for the article.