Need to create additional links between nodes

I have created a D3 hierarchical chart and it is perfect. But my requirement is, i want to create a path between nodes which are not related.

in the tree (please refer the attached image), i want to show the additional links / edges dynamically for eg. in the tree want to create a link between Pre-req LO 07 and LO8, similarly other edges. Please help me to fix it.

did you get success to make connection between sibling nodes ?