How we cite our quotes: (Chapter.Paragraph)
Quote #1
"Just respect the rules and we'll get along fine." (2.15)
Famous last words, Grandpa. Setting out rules for kids to follow might seem simple, but things are rarely that easy. Of course, it's a little odd that Grandpa's hoping the kids will think outside the box enough to taste the milk and thus be exposed to magic. But there's no rule against drinking milk, is there? Just exploring where they shouldn't be.
Quote #2
"Don't blame me," Grandpa said. "You locked yourself up by disregarding the rules." (4.150)
For every action, there is a consequence, and this is especially true when it comes to breaking the rules in Grandpa's household. He wants to confine the kids to their rooms for the rest of their stay, and in the end that might be safer for them—but Kendra manages to argue for a reduced punishment, saying that they'll follow the rules from then on. Do they?
Quote #3
"The fundamental premises of the law are mischief for mischief, magic for magic, violence for violence. They will not initiate trouble unless you break the rules." (5.152)
Grandpa lays it out for Kendra and Seth: if humans follow the rules while interacting with magical beings, they should be safe. Emphasis on the should. As we see later in the book, there are ways to break rules without even realizing it (like when Seth captures a fairy, or when he opens the window on Midsummer Eve… hm, funny how Seth seems to be the one breaking all the rules around here).