diff --git a/app/Providers/ValidationServiceProvider.php b/app/Providers/ValidationServiceProvider.php
index 5ee904d20..50468c8d7 100644
--- a/app/Providers/ValidationServiceProvider.php
+++ b/app/Providers/ValidationServiceProvider.php
@@ -80,9 +80,20 @@ class ValidationServiceProvider extends ServiceProvider
                 return $count < 1;
             }
         });
-
-        // Unique if undeleted for two columns
-        // Same as unique_undeleted but taking the combination of two columns as unique constrain.
+        
+        /**
+         * Unique if undeleted for two columns
+         *
+         * Same as unique_undeleted but taking the combination of two columns as unique constrain.
+         * This uses the Validator::replacer('two_column_unique_undeleted') below for nicer translations.
+         *
+         * $parameters[0] - the name of the first table we're looking at
+         * $parameters[1] - the ID (this will be 0 on new creations)
+         * $parameters[2] - the name of the second table we're looking at
+         * $parameters[3] - the value that the request is passing for the second table we're
+         *                  checking for uniqueness across
+         *
+         */
         Validator::extend('two_column_unique_undeleted', function ($attribute, $value, $parameters, $validator) {
             if (count($parameters)) {
                 $count = DB::table($parameters[0])
@@ -96,6 +107,27 @@ class ValidationServiceProvider extends ServiceProvider
         });
 
 
+        /**
+         * This is the validator replace static method that allows us to pass the $parameters of the table names
+         * into the translation string in validation.two_column_unique_undeleted for two_column_unique_undeleted
+         * validation messages.
+         *
+         * This is invoked automatically by Validator::extend('two_column_unique_undeleted') above and
+         * produces a translation like: "The name value must be unique across categories and category type."
+         *
+         * The $parameters passed coincide with the ones the two_column_unique_undeleted custom validator above
+         * uses, so $parameter[0] is the first table and so $parameter[2] is the second table.
+         */
+        Validator::replacer('two_column_unique_undeleted', function($message, $attribute, $rule, $parameters) {
+            $message = str_replace(':table1', $parameters[0], $message);
+            $message = str_replace(':table2', $parameters[2], $message);
+
+            // Change underscores to spaces for a friendlier display
+            $message = str_replace('_', ' ', $message);
+            return $message;
+        });
+
+
         // Prevent circular references
         //
         // Example usage in Location model where parent_id references another Location:
diff --git a/resources/lang/en/validation.php b/resources/lang/en/validation.php
index 85e844781..57e354f07 100644
--- a/resources/lang/en/validation.php
+++ b/resources/lang/en/validation.php
@@ -90,6 +90,7 @@ return [
     ],
     'string'               => 'The :attribute must be a string.',
     'timezone'             => 'The :attribute must be a valid zone.',
+    'two_column_unique_undeleted' => 'The :attribute must be unique across :table1 and :table2. ',
     'unique'               => 'The :attribute has already been taken.',
     'uploaded'             => 'The :attribute failed to upload.',
     'url'                  => 'The :attribute format is invalid.',