In response to some of the discussion on the forums and russell's blog, I'm demonstrating a more "elegant" way to set up parent and child movement in Flowgraph.
See picture:
And Video:
http://www.youtube.com/watch?v=uZp5IWXeu-4
And aside:
If you are attaching and detaching children in FG, make sure you set "KeepTransform" to "1" so that your objects don't "disappear". If left default "0", then you'll be taking your entity's global position and making it their new local position (which is far away!).