It starts early "Etiquette"

Children seem to be especially designed to listen to language. In fact, they don’t even wait until they are born to start. Speech can be heard in the womb-not precisely enough to make out individual sounds, but clearly enough to identify the basic rhythm and certain features of the speaker’s voice. And yet-to-be-born children are evidently listening: at birth, they prefer their mother’s voice to other female voices, they prefer the language of their parents over other languages, and they are able to recognize that an English sentence does not sound the same as a French sentence.