diff --git a/book/validation.rst b/book/validation.rst
index 74e0c97bfaf..2f2a1d6b736 100644
--- a/book/validation.rst
+++ b/book/validation.rst
@@ -954,7 +954,7 @@ username and the password are different only if all other validation passes
                 - Strict
             getters:
                 passwordLegal:
-                    - 'True':
+                    - 'IsTrue':
                         message: 'The password cannot match your username'
                         groups: [Strict]
             properties: