This is called "code switching" and is just something that happens (with all people, but particularly children) in multilingual environments. A former teacher o

This is called "code switching" and is just something that happens (with all people, but particularly children) in multilingual environments. A former teacher of mine was writing her dissertation on it when the students she was studying went home for holidays and returned speaking only their native language. http://en.wikipedia.org/wiki/Code-switching http://en.wikipedia.org/wiki/Code-switching