Identifying movieclip using another movieclip

Is there a way to identify a movieclip by its relationship to another. That is to say I have one movie clip “ball_mc” that moves randomly around the screen over photos (photo1_mc, photo2_mc . . .), I want as ball_mc passes over a photo?_mc for a textbox to display the name of that particular photo?_mc. Can someone point me in the right direction?
Thanks!