Passing data between parent child window

I was wondering how to pass data between windows that are opened by Adobe AIR.

In this application, the parent window opens another native child window. The child window has some text under the DIV section. If the child window is already opened, the parent window should just pass the data to the child window and the child window displays the data.

Also I want to trigger an event in the parent window from the child window and a data passed from the child window. How do we do this?

Thanks
Binu