When new ways of speaking emerge in language contact situations, questions abound as to the cognitive and sociolinguistic processes involved, and who the primary agents of change are. There is usually little empirical data on the speech of adults or children at the time of emergence of mixed languages and Creoles, because many of them developed long ago. But in the case of the Australian mixed language Light Warlpiri, which emerged only in the last forty years or so, we have empirical data on the speech of each generation involved, which allows us to model the process of language emergence.

In this talk I show how Light Warlpiri emerged in a two-stage process, and discuss the roles of adults and young children in its emergence. I provide empirical data to suggest that children’s cognitive processing during language acquisition in complex, fluid multilingual environments, with ultimately unusual outcomes, can be the same as in any other language acquisition situation. The configuration of the sociolinguistic context, and the type of input to the children, allow common processes to lead to a less common outcome.