Vector from Orientation - bge Python question.

This is probably a dumb question…

I need a vector value for an applyForce() in the bge.
The force should be in the direction of the orientation of an object. (ob.worldOrientation)
basically I would need to return the point on a unit sphere that intersects the local Z of the object.

Does that make any sense? If so- what’s the easiest way to do this? Does blender have something in the mathutils I’m missing.

Thanks for any help and sorry if the explanation isn’t great.

I guess a better explanation would be this:

Say I set a child object 1 unit above a parent object.

As I rotate the parent object I can use
obParent.getVectTo(obChildObject)
to get the vector I need.

How could I achieve this without using a child object? How could I get the vector from just the parent objects orientation?