iTween colliders

I was hoping someone could help figure out how to have to objects share a collider. No doubt I am wrong here but I am new.

My problem is I have two objects a plane and a box.

The plane moves up from the screen (iTween.MoveTo) when the mouse is over (OnMouseEnter), and the box is a child of the plane so it moves with it.

But I have a problem when I move the mouse over the box, the plane wants to recede(OnMouseExit) while box tries to expand(iTween.ScaleTo).

I am using really simple iTween script for the two objects, but cant seem to get the plane to stay in focus when I hover over the box.

Im trying to make a GUI type interface: When you slide the mouse pointer to side of the screen a table pops out whith objects on it that expand when the mouse is over them.

Any help would be awesome!

When you say "stay in focus" do you mean how to keep a consistent hit-area for the "button" of the geometry since its moving?