diff --git a/docs/releases/1.6.1.txt b/docs/releases/1.6.1.txt
index 128a2e99c5..5c9bd1e1c5 100644
--- a/docs/releases/1.6.1.txt
+++ b/docs/releases/1.6.1.txt
@@ -12,3 +12,6 @@ Bug fixes
 =========
 
 * Fixed ``BCryptSHA256PasswordHasher`` with py-bcrypt and Python 3 (#21398).
+* Fixed a regression that prevented a ``ForeignKey`` with a hidden reverse
+  manager (``related_name`` ending with '+') from being used as a lookup for
+  ``prefetch_related`` (#21410).