diff --git a/Kernel/Thread.h b/Kernel/Thread.h
index d668f5bd76..45a170e05d 100644
--- a/Kernel/Thread.h
+++ b/Kernel/Thread.h
@@ -75,9 +75,11 @@ public:
 
     class FileDescriptionBlocker : public Blocker {
     public:
-        explicit FileDescriptionBlocker(const FileDescription&);
         const FileDescription& blocked_description() const;
 
+    protected:
+        explicit FileDescriptionBlocker(const FileDescription&);
+
     private:
         NonnullRefPtr<FileDescription> m_blocked_description;
     };