Controlling a MovieClip within a MovieClip

Boy, dont I feel like the village idiot! Well, I made a movie clip dropdown menu(bioClip). It is animated. I made another movie clip (buttonTwo), so I could animate it, and placed it in the dropdown menu.

I have tried placing the code on the maintimeline, in the timeline of the dropdown movie clip, but I get the same message:

“TypeError: Error #1009: Cannot access a property or method of a null object reference.
at control2_fla::bioClip_2/control2_fla::frame1()”

If anyone has seen this before, maybe they could point me in the right direction. I guess I am missing some type of “addChild” or “objectExists” or “comeOnComputerAndRecognizeTheGoddangObject” or something, based on the “null object” thing. I am super-new to this as far as AS goes, so, if you have any information, please explain it to me as if I am not too bright. :thumb2:

Thank You.