The One-Parent-One-Language Approach. What is it?

In the first part of this chapter we look at the origins of the one-parent-one-language (OPOL) approach. Who first coined the phrase? How has it changed over the last century? Who were the early pioneers of child bilingualism? We hear about Jules Ronjat and Werner Leopold, and how their detailed notes on their children helped us see how a child becomes bilingual. Several decades later several linguists such as George Saunders, Traute Taeschner and Charlotte Hoffmann produced more case studies, giving us fascinating insights into a child's life with two or more languages. What do modern parents think OPOL is and how do they apply it within their families? We hear their comments and views on OPOL nowadays.

The second part of the chapter investigates mixing and code-switching in children, which can cause conflict within bilingual families. Should a child mix languages? Is code-switching acceptable or useful? When does language mixing become code-switching? We hear what parents think about their children's code-switching alongside some studies of this linguistic behaviour. Most important is the recent approach of looking at the whole family's interactions and how each parent or sibling can affect a child's choice of using one language or switching.

Part One: The Origins of the OPOL Approach – Maurice Grammont and his Advice to Ronjat

The original term came from a French linguist, Maurice Grammont, who published a book in 1902 titled Observations sur le langage des enfants (Observations on Children's Language), in which he introduced the idea of une personne; une langue. Literally translated from the French as one person; one language, Grammont theorised that by strictly separating the two languages from the beginning the child would subsequently learn both languages easily without too much confusion or mixing of languages. By associating each language with a specific person the chances of mixing languages are significantly reduced. Furthermore, by using his or her own language each parent gives an example of adult language use. They also have the opportunity to form a natural emotional relationship with the child through their language.

Several years later Grammont's friend and fellow linguist Jules Ronjat sought advice from him. Ronjat was married to a German national living in Paris and they had a son, Louis, born in 1908, whom they wished to bring up bilingually. Ronjat reports Grammont's advice (1913: 3):

Nothing has to be taught to the child. You must simply speak to him, when there is something to be said, in one of the two languages that you want him to learn. But there is a key factor, and that is that each language must be represented by a different person, you, for example always speak French to him, his mother German. Never reverse these roles. In this way, when he begins to speak he will speak the two languages without being conscious of doing so and without having made any special effort to learn them. (Translated from French).

Ronjat went on to record and transcribe Louis' language development until he was four years and ten months old. He then published this linguistic biography in Le Developpement du langage: observe chez un enfant bilingue (The Development of Language: Observations of a Bilingual Child). Ronjat recommended what he called the Grammont Formula in his description of Louis' positive child bilingualism. He cited the continual use at home of two languages from birth as a major factor in achieving bilingualism and noted that Louis had acquired and mastered two languages in a similar phonological order to that of the average monolingual child. The child learnt German from both his mother and his German nanny, and French from the father and from the French-speaking community he grew up in. Ronjat also spoke German to his wife thus giving her linguistic support as the minority speaker. Louis rarely mixed languages and after age of three was clearly aware of the difference in his two languages and would change languages to adjust to the person he was talking to. We even have some information on Louis Ronjat as a teenager, aged 15; he apparently remained bilingual throughout preferring to read in German and take his school examinations in French.

In the 1920s and 1930s several laboratory studies showed bilingualism to be negative because it risked overloading a child's mental capacity. These studies have now been disqualified due to dubious research techniques and IQ testing in only one language, which was unsuitable and unfair for young children. The only other well-documented study of this period was by Pavlovitch, a Serbian linguist, living in Paris with his Serbian wife. He compiled a one-year study in 1920 on his own son, Dusan. He recorded data from the age of 13 months onwards on Dusan, who had previously only heard Serbian from his parents. They then employed a close family friend to speak only French to the child for several hours a day. The child subsequently spoke good French, although in this case it was quite a probable outcome as the family was living in Paris. Nonetheless it shows the effect that a close one-to-one relationship can have and how it can facilitate language learning.

Twenty years later the same parental strategy of une personne; une langue was successfully applied by another parent-linguist Werner Leopold, who was familiar with Ronjat's case study. Leopold himself was born in London to German parents, who moved back to Germany when he was three years old. After completing his schooling in German he moved to America and married a third-generation German-American. When their first daughter, Hildegard, was born in 1930 they decided to bring her up bilingually. Leopard spoke only German while his wife spoke English although she understood and could speak German. In fact, in comparison to the Ronjat family, there were several changes in parental language use within the Leopold house with Werner frequently using English and his wife using German when holidaying in Germany. Although Mrs Leopold understood German she preferred not to speak it in America, but nonetheless did use it when visiting family in Germany.

Leopold's diary study from age two months to age seven (with additional observations up to age 14)...