how to access parent dynamic textx

I have main screen that has Loader to load SWF files. Within these SWF files there is also Loader that loads SWF files.

                                   loads                                   loads

So  Main Screen  ============>  SWF files  ==============> SWF files

          |                                                                                               |

          |                                                                                               |

          |                                                                                               |

  dynamic text                                                         how to access from here the dynamic text

The main Screen has MovieClip (which is called page) that contains the dynamic text(which is called left_txt )

I tried this:

parent.page.left_txt.text = "Moora";

and

MovieClip(parent).page.left_txt.text = "Moora";

but it didn't work.

Waiting for your help.