Attached Nodes

I may need to add nodes to other nodes without links. (See Picture below) Is it possible?

The yellow boxes are really input and output to and from the operation represented by the Blue Node.

If you are going to connect links to them, those look like ports to me.

If you don't need to worry about any resizing going on, you can just allocate GoPorts, set their Bounds, and Add them to your node.
If the size of the node might change, you should override LayoutChildren so that you can make sure the ports are positioned where you want them to be.