Ordered Tree in C++

The C++ STL apparently is missing an ordered tree data structure. See here. Boost is also missing an ordered tree, but it does have an "un"ordered one, Property Tree where the data is ordered by insertion. I want the order to be irrespective of memory.

The boost page on Property Trees says that this is conceptually the boost::ptree structure.

struct ptree
{
   data_type data;                         // data associated with the node
   list< pair<key_type, ptree> > children; // ordered list of named children by insertion
};

I want to extend boost to keep track of order.

Is this the correct way?

class ordered_ptree : public boost::property_tree::ptree {
public:
  ordered_ptree(int id) : _id{id}{};

 protected:
  int _id;
};