diff --git a/core/includes/theme.inc b/core/includes/theme.inc
index 9b89250..9df6626 100644
--- a/core/includes/theme.inc
+++ b/core/includes/theme.inc
@@ -553,6 +553,11 @@ function template_preprocess_datetime_form(&$variables) {
     $variables['attributes']['class'] = (array) $element['#attributes']['class'];
   }
 
+  // Unset #prefix and #suffix here to avoid duplicate, since they already are
+  // in datetime_wrapper.
+  unset($element['#prefix']);
+  unset($element['#suffix']);
+
   $variables['content'] = $element;
 }