diff --git a/code/controllers/CMSMain.php b/code/controllers/CMSMain.php
index 12f19ccb..59b3481c 100644
--- a/code/controllers/CMSMain.php
+++ b/code/controllers/CMSMain.php
@@ -250,7 +250,8 @@ class CMSMain extends LeftAndMain implements CurrentPageIdentifier, PermissionPr
 			if($defaultChild != 'Page' && $defaultChild != null) 
 				$def[$class]['defaultChild'] = $defaultChild;
 			
-			$id = SiteTree::get_by_link($obj->defaultParent())->ID;
+			$defaultParent = $obj->defaultParent();
+			$id = $defaultParent ? SiteTree::get_by_link($defaultParent)->ID : null;
 			$defaultParent = $id ? SiteTree::get_by_link($obj->defaultParent())->ID : null;
 			
 			if ($defaultParent != 1 && $defaultParent != null)  $def[$class]['defaultParent'] = $defaultParent;