diff --git a/user_relationship_mailer/user_relationship_mailer_defaults.inc b/user_relationship_mailer/user_relationship_mailer_defaults.inc
index e66489a..9b12951 100644
--- a/user_relationship_mailer/user_relationship_mailer_defaults.inc
+++ b/user_relationship_mailer/user_relationship_mailer_defaults.inc
@@ -73,6 +73,9 @@ function user_relationship_mailer_replacements(&$relationship) {
     $replacements['@deleted_by_uid']  = $deleted_by->uid;
   }
 
+  // Allow other modules to modify these replacements
+  drupal_alter('user_relationship_mailer_replacements', $replacements);
+
   return $replacements;
 }