public function set_parent(navigation_node $parent) {
        // Set the parent (thats the easy part)
        $this->parent = $parent;
        // Check if this node is active (this is checked during construction)
        if ($this->isactive) {
            // Force all of the parent nodes open so you can see this node
            $this->parent->force_open();
            // Make all parents inactive so that its clear where we are.
            $this->parent->make_inactive();
        }
    }