diff --git a/sane/gb_json.cpp b/sane/gb_json.cpp
index 0964150..32d3cbb 100644
--- a/sane/gb_json.cpp
+++ b/sane/gb_json.cpp
@@ -510,9 +510,9 @@ namespace gb
     }
     json* json::first_child(void)
     {
+        cur_child_ = 0;
         if (type_ == VAL_TYPE_OBJECT || type_ == VAL_TYPE_ARRAY)
         {
-            cur_child_ = 0;
             if (arr_val_.size())
             {
                 arr_val_[0]->add_ref();
@@ -521,7 +521,10 @@ namespace gb
             }
         }
 
-        return nullptr;
+        // leaf node, return self
+        add_ref();
+
+        return this;
     }
     json* json::next_child(void)
     {
@@ -1597,7 +1600,15 @@ namespace gb
                 jsn_->set_value("ver", ver);
             }
 
-            std::string cont(jsn_->to_string());
+            std::string cont("");
+            if (jsn_->is_leaf_node())
+            {
+                jsn_->value(cont);
+                cont.insert(0, "{\"" + jsn_->key() + "\":\"");
+                cont += "\"}";
+            }
+            else
+                cont = jsn_->to_string();
             if (b64)
             {
                 gb::base64	b64;