Elder Amberites
List of Oberon's Children by Mother.
The first nine sons of Oberon, other than Oscric and Finnido are the "Nine Princes" from the title of the first book.
—- after Random the rest are not as acknowledged or considered "Elder Amberites" on the same level as the earlier ones.
There are probably many, many more. A pattern ghost of Oberon once bragged to Merlin that the number was something like 47.