diff --git a/headers/private/storage/DiskDevice.h b/headers/private/storage/DiskDevice.h
index 5ad4b949f6..0ed35f923a 100644
--- a/headers/private/storage/DiskDevice.h
+++ b/headers/private/storage/DiskDevice.h
@@ -7,7 +7,6 @@
 #define _DISK_DEVICE_H
 
 #include <DiskDeviceVisitor.h>
-#include <Messenger.h>
 #include <ObjectList.h>
 
 class BPartition;
@@ -64,6 +63,7 @@ private:
 	bool _AddSession(BSession *session);
 
 private:
+	friend class BDiskDeviceList;
 	friend class BDiskDeviceRoster;
 
 	BObjectList<BSession>	fSessions;
diff --git a/headers/private/storage/Partition.h b/headers/private/storage/Partition.h
index a4dc6d8caa..e7f8c2461f 100644
--- a/headers/private/storage/Partition.h
+++ b/headers/private/storage/Partition.h
@@ -79,6 +79,7 @@ private:
 	void _SetSession(BSession *session);
 
 private:
+	friend class BDiskDeviceList;
 	friend class BSession;
 
 	BSession				*fSession;
diff --git a/headers/private/storage/Session.h b/headers/private/storage/Session.h
index 1290d66fa8..797c484852 100644
--- a/headers/private/storage/Session.h
+++ b/headers/private/storage/Session.h
@@ -71,6 +71,7 @@ private:
 
 private:
 	friend class BDiskDevice;
+	friend class BDiskDeviceList;
 
 	BDiskDevice				*fDevice;
 	BObjectList<BPartition>	fPartitions;