Many young children with two first languages from birth develop a good level of proficiency in only one of their languages, and not in the other. They may even show signs of language attrition before reaching primary school. Such findings contradict claims of guaranteed successful L2 learning in young children.
It is often claimed that all "normally developing" children reach "full" proficiency in their first language. Also, it is often said that in order to learn a language well, one should start learning it as early as possible, if not from birth, then in child care or preschool. Parents all over the world literally "buy" into this and pay large sums of money to place their children in bilingual preschools. Others even start speaking a foreign language to their infant children to ensure successful early foreign language learning. This presentation shows that, contrary to these claims of guaranteed successful L2 learning in very young children, many children who hear two first languages from birth develop a good level of proficiency in only one of their languages, and not in the other. They may even show signs of language attrition before they reach primary school. Such findings challenge the notion that being exposed to a language early in life automatically leads to successful language learning. Age is clearly not a critical factor here. Rather, other factors than age are relevant, such as the frequency and quality of language input, and children's need to use both languages in communication.
