Let's say I have a cube and a sphere, and I make the cube the parent of the sphere. Then I link-duplicate both the cube and sphere with AltD. Then I start moving/rotating/etc. the duplicates around in object mode, together as a unit.
Later, I discover that I want to change the position of the sphere (child) with respect to the cube (parent). I re-position the original sphere, but the duplicate sphere does not change position.
I can manually copy the transform values from the original to the duplicate, but is there a way to automatically have the transform values be linked?