diff --git a/conditional_fields.module b/conditional_fields.module
index 4d0b87c..f896b04 100755
--- a/conditional_fields.module
+++ b/conditional_fields.module
@@ -1292,10 +1292,15 @@ function conditional_fields_set_required_field_recurse(&$item) {
  * Unset the #required property and set a #conditional_fields_required property for custom validation.
  */
 function conditional_fields_custom_required_field(&$field) {
-  if ($field['#required']) {
+  if (isset($field['#required']) && $field['#required']) {
     unset($field['#required']);
     $field['#conditional_fields_required'] = TRUE;
+
+    if ($field['#type'] == 'radios' && $field['#default_value'] === NULL && isset($field['#needs_validation']) && $field['#needs_validation']) {
+      unset($field['#needs_validation']);
+    }
   }
+
   foreach (element_children($field) as $child) {
     conditional_fields_custom_required_field($field[$child]);
   }