How to control a movie from another movie?

I am new to actionscript any my questions may be unclear, please level with me.

I have a movie A, from that movie I have a button that loads another movie B.
The button actionscript is

loadMovieNum(“name.swf”, 1)

I want to know if its possible from the loaded movie, movie B, to have a button that control some parameters of movie A?

Thank you.