Clips within duplicated clips

If I were to use actionscripting to duplicate a movie clip that contained another movie clip, what would the name of the inner movie clip be?

For instance, say I have the a movie clip called shapesClip, and inside shapesClip I have circleClip. I then duplicate shapesClip, and then want to change the _y property of circleClip, but in the new shapesClip, not the old one. How would I refer to circleClip?

Thanks!