Simplify the following text for a Grade 6 native English-speaking person.
Original: Percy and Nico , the son of Hades , sneak out of camp , and meet Hestia , who shows Percy part of Luke 's past , after they meet Luke 's mother , who tried to become the Oracle , and was thus driven insane by a curse of Hades ' working .
Simplified: Percy and Nico sneak out of camp , and meet Hestia , who shows Percy part of Luke 's past , and they meet Luke 's mother .