Is Nebuchadnezzar related to King Belshazzar?

In the Bible, Belshazzar is portrayed as the son of Nebuchadnezzar (king of Babylon). However, later findings suggest that Belshazzar was the son of Nebuchadnezzar's successor Nabodinus and Nitochris (who is suggested to be the daughter of Nebuchadnezzar). Generally, both account suggests that they were related by blood. It is also certain that both Nebuchadnezzar and Belshazzar were kings of Babylon and that Belshazzar's reign was after Nebuchadnezzar's.