diff --git a/Controller/BackendController.php b/Controller/BackendController.php
index e4e0974..65cef86 100755
--- a/Controller/BackendController.php
+++ b/Controller/BackendController.php
@@ -171,14 +171,15 @@ final class BackendController extends Controller
             $tree[$ref][$component->getId()]['obj'] = $component;
 
             $parent = $component->parent->getId();
-            if (!($component instanceof Position) // parent could be in different department then ignore
-                || (!($component->parent instanceof NullPosition) && $component->parent->department->getId() === $component->department->getId())
+            if ($parent !== 0
+                && (!($component instanceof Position) // parent could be in different department then ignore
+                    || $component->parent->department->getId() === $component->department->getId()
+                )
             ) {
                 if (!isset($tree[$ref][$parent])) {
                     $tree[$ref][$parent] = ['obj' => null, 'children' => [], 'index' => 0];
                 }
 
-                // For some stupid reason the next line is too complicated for phpstan and the error it creates is insane/wrong!
                 /** @phpstan-ignore-next-line */
                 $tree[$ref][$parent]['children'][] = &$tree[$ref][$component->getId()];
             }
diff --git a/Models/Unit.php b/Models/Unit.php
index c0a98bf..bde2faa 100755
--- a/Models/Unit.php
+++ b/Models/Unit.php
@@ -54,10 +54,10 @@ class Unit implements \JsonSerializable
     /**
      * Parent
      *
-     * @var null|Unit
+     * @var Unit
      * @since 1.0.0
      */
-    public ?self $parent = null;
+    public self $parent;
 
     /**
      * Description.
diff --git a/tests/Bootstrap.php b/tests/Bootstrap.php
index d46fd31..b5d36a8 100755
--- a/tests/Bootstrap.php
+++ b/tests/Bootstrap.php
@@ -257,6 +257,25 @@ $CONFIG = [
         'root'  => '/',
         'https' => false,
     ],
+    'app'      => [
+        'path'    => __DIR__,
+        'default' => [
+            'app'   => 'Backend',
+            'id'    => 'backend',
+            'lang'  => 'en',
+            'theme' => 'Backend',
+            'org'   => 1,
+        ],
+        'domains' => [
+            '127.0.0.1' => [
+                'app'   => 'Backend',
+                'id'    => 'backend',
+                'lang'  => 'en',
+                'theme' => 'Backend',
+                'org'   => 1,
+            ],
+        ],
+    ],
     'socket'   => [
         'master' => [
             'host'  => '127.0.0.1',