Use the Unlink Selection button to remove the hierarchical relationship between two objects.

Select and Link and Unlink buttons on the toolbar.
Unlink Selection detaches a child object from its parent object.
Tip: You can also link and unlink hierarchies in
Schematic View.
Procedures
To unlink a child object from a parent object:
- Select the child object you want to unlink.
- Click Unlink Selection.