These changes reflect the fact that the parents of these two children are divorced and are undergoing adjustments on the custody of their children. This is often the most complicated part of filing for a divorce, because children are uprooted from their family backgrounds and are forced to live in a different situation from which they were accustomed to.
Nigeria belongs to continent Africa. The Africans have a wonderfull oral tradition. So, your answer is Nigerian storytelling has historically been an D. oral tradition.