diff --git a/resources/lang/en/validation.php b/resources/lang/en/validation.php
index c7a1ecf0..992122e8 100644
--- a/resources/lang/en/validation.php
+++ b/resources/lang/en/validation.php
@@ -60,6 +60,7 @@
     'regex'                => 'The :attribute format is invalid.',
     'required'             => 'The :attribute field is required.',
     'required_if'          => 'The :attribute field is required when :other is :value.',
+    'required_unless'      => 'The :attribute field is required unless :other is in :value.',
     'required_with'        => 'The :attribute field is required when :values is present.',
     'required_with_all'    => 'The :attribute field is required when :values is present.',
     'required_without'     => 'The :attribute field is required when :values is not present.',