What is the climax of the book

When Ruby finishes her story, both Ivan and Bob start to cry. They tell her it is good to talk about sad things. That night, Ruby cannot sleep because her Tuskday is in the morning. She wakes up early and tries to sneak out the hold to run away, but she gets stuck and starts to cry.

Aunt Akello finds Ruby and tells her a riddle to lighten the mood. Then she uses her tusks to help Ruby get out of the fence unharmed. Aunt Akello tells Ruby that she, too, grew up in Africa. Ruby confesses that she hates her tusks, and Aunt Akello says she understands. She explains that humans want elephant tusks to make objects out of, but insists that tusks are useful and worthy of celebration.