How to access armature of a child object?

Hi, I'm trying to figure out how to bones of an armature that is part of a model that is a child object of the player object. Basically what I am trying to do is to make the "keyBone" bone rotate via a script, but I don't know how to access it. This is a rough depiction of how my hierarchy is structured: Player Obj -> Model -> Armature -> body -> keyBone I really appreciate any help here, this has been bugging me for a while and I can't seem to find the answer. Thanks, H. Chappee