When Kendra and Seth first arrive at their grandparents' place, there are all these annoying rules they have to follow: don't go into the woods, keep out of the barn, and so on. But we all know that in fantasy and fairy tales, rules are practically made to be transgressed—and once the kids are clued in about the magic of Fablehaven, there are even more rules to follow. Do no mischief, do no harm, stay inside certain boundaries, and things will all be fine… right? Not quite.
Turns out that Seth isn't so good at following the rules, and when push comes to shove, Kendra will also strategically break the rules. But it's all cool with us, since Fablehaven would be a pretty boring book if everyone were obedient all the time.
Kendra and Seth are polar opposites when it comes to rules-following behaviors.
Rules are the only thing that holds Fablehaven together.
Families are strange sometimes. You know, like how you can be related to someone by blood and have no idea that they're running a preserve for mystical creatures. This is pretty much exactly what happens to Kendra and Seth in Fablehaven when they go to stay with their grandparents for a couple of weeks so that their parents can go on a cruise with other relatives.
We see family as a theme in other ways too, though, like the huge contrasts between Kendra and Seth. For all that they're siblings, these kids are pretty much like night and day: Seth breaks rules left and right, while Kendra is usually pretty obedient—stuff like that. Family is also important because family members tend to have one another's backs, like when Kendra is so determined to rescue her family that she takes some pretty big risks. So maybe family's not all that bad, or at least not that weird (or maybe family being weird doesn't make family bad).
Every family has its secrets, but Kendra and Seth's family has more secrets than most others.
Kendra is the bravest person in her family.
Well, derp, of course a book about a preserve for magical creatures deals with the supernatural—it's how exactly it does so that's the interesting part. As Kendra and Seth learn about the magic that exists at their grandparents' place, they find out that magic is very rule-governed. Magic critters aren't necessarily good or evil, but more or less chaotic or ordered—and there are a ton of magic creatures to get to know: satyrs, trolls, fairies, brownies, golems, demons, imps, and so on—plus a bunch we don't even get to meet.
Magic is kinda like the gift that keeps on giving: there's always more to it. Which is great, since Fablehaven is just the first book in the series.
Magic is not very mysterious in Fablehaven, since it follows its own system of rules that can be learned and followed.
Kendra's innocence makes her the perfect person to interact with high-level magic beings like the Fairy Queen.
Stuff changes into other stuff a lot in Fablehaven. Humans change into chickens, or mutant-walruses, or humans who are no longer quite normal and can see magical critters without having first consumed special milk. Fairies change into imps (and back again), and both fairies and imps alike can go from tiny and wee to human-sized.
Inner transformations happen too, like when Seth and Kendra become closer since the experience of being at the preserve is totally unique and teaches them some life lessons (though it's debatable whether Seth will ever learn to be less impulsive and rule-breaky). Bottom line? Transformation's pretty important to the story in Fablehaven. Chew on that, young Jedi.
Magical transformations are just a part of daily life at Fablehaven.
In Fablehaven, the power to transform humans into other shapes, or to mess with the size of fairies, is dangerous, and shouldn't be messed with.
Courage is kind of a prerequisite for getting stuff done in Fablehaven. Having to face big scary monsters obviously requires some amount of bravery, and let's not even start in on how freaky Midsummer Eve is. The fact that Kendra and Seth don't run screaming from the preserve when they learn what's in store for them shows that they're pretty brave.
We also see, however, that there's a fine line between brave-brave and stupid-brave—Seth walks it quite frequently. His bravery is helpful in situations like getting up to Nero's place, but less helpful when he acts out and annoys witches, fairies, and pretty much any other magical creature we can name. Kendra, who doesn't really think of herself as brave, actually saves the day by being courageous enough to take a giant risk, and thus rescue her family. Who knew, right? Probably not Kendra, that's for sure.
Kendra is not brave, only desperate.
True courage is almost indistinguishable from foolishness (especially when it comes to Seth).
When Kendra and Seth learn the truth about Fablehaven, they immediately start wondering which magical creatures are good and which are evil—problem is, there's not a straightforward answer to that question. According to Grandpa, fairies are allowed in the house and garden, but not because they're good; and naiads drown humans, but not because they're evil. Magical creatures just kind of are what they are, and notions of human morality don't really apply to them.
But when we start talking demons and witches, that's a whole other topic. In Fablehaven, sometimes there are creatures so chaotic and violent that they are, for all intents and purposes, evil. And Seth and Kendra get to face these creatures too. Oh joy.
In Fablehaven as elsewhere, great power can corrupt you and turn you evil.
Good and evil are human constructs, and that's why they don't apply to magical creatures.
The supernatural world hidden inside Fablehaven is full of appearances, both beautiful and hideous, enticing and misleading. Kendra and Seth learn this the hard way: the fairies may be exotic and lovely to look at, but they're quick to take revenge when Seth accidentally turns one of them into an imp (speaking of appearance-issues, fairies are universally beautiful and imps are universally ugly).
Magic can be used to alter someone's appearance too, as in cases of magical transformations, or with spells to make one look young and appealing. And aging in its own right is another appearance-changer (you'll want to talk to Lena about that one). In short, appearances contain a lot of information in Fablehaven… whether you know how to decipher their code is another question entirely.
Appearances in Fablehaven are more deceptive often than not.
The more magically-enhanced an appearance is in Fablehaven, the more dangerous the creature wearing it is.
Kendra and Seth are young 'uns in Fablehaven, but their experiences at their grandparents' place are shaped by events that occurred long ago—like when the demon Bahumat was imprisoned on that land (similar deal with Muriel's imprisonment, though that happened less-long-ago). Plus some recent-but-still-past events are also important—like Grandma being transformed into a chicken, and whatever diabolical plans Muriel put into motion to free Bahumat.
And then there's all the important stuff about memory: how our memories define us, and what our memories can teach us. Case in point: Lena. When she's human, she can hang onto and treasure her memories, but as a naiad, she's stuck in a timeless existence where memories don't really matter. Which one's better? We're not sure. You wanna go to the naiad pond and try to find out?
It is better to be mortal and have memories than to be immortal and not remember anything, like the naiads and fairies of Fablehaven.
Coming to Fablehaven without knowing anything of its history puts the kids at a big disadvantage.