234 Tree question

Hi all,

If you have a 234 tree setup like this:

Code:

---

class Tree{

    private:

        class Node{

            private:

                class Key{

                };

            public:

        };

    public:
};

---

Who should "promote" a Node? Would a node promote itself or would a tree promote a node?

If you haven't really ever studied 234 trees here's a quick look at what they're all about:
234trees