At the tender age of twelve, Sadie already knows how to rebel. Her philosophy is: "when someone says I forbid it, that's a good sign it's worth doing" (7.2).
Sadie doesn't do well with authority figures. When the detective is questioning her about her father's acts in the British Museum, Sadie notes: "I could hear in his voice that he was resisting the urge to strangle me. Strangely, I get this a lot from adults" (3.56). She could clearly teach a class called Angering Adults for Fun and Profit.
Sadie's a nonconformist, and you can tell based on the clothes she wears. When Carter sees his sister for the first time in half a year, he gives us a handy description: "[S]he takes after our mom, who was white, so Sadie's skin is much lighter than mine. She has straight caramel-colored hair, not exactly blond but not brown, which she usually dyed with streaks of bright colors. That day it had red streaks down the left side. Her eyes are blue…just like our mom's" (1.7).
That day, Sadie's wearing a leather jacket, combat boots, and battered jeans. It's as though she couldn't be bothered to dress up for seeing her father and brother, even though it only happens twice a year.
Part of the reason for her rebelliousness is her odd family background. She comes from a mixed-ethnicity family, and a lot of people don't understand that: "After a while one learns that blending in simply doesn't work. If people are going to single me out, I might as well give them something to stare at" (15.9). Sounds like a solid philosophy. For a teenager, at least.
Sadie thinks of herself as strong and capable, but it's not like she's immune to emotions. During the Great Fruit Bat Chase in Paris (how's that for a band name?), she feels the toll events are taking on her: "I realized I was crying. I hated to, but shock and fear were starting to overwhelm me" (19.21). It's okay, Sadie, no one's perfect.
Okay, maybe Sadie's not a sadist in the traditional sense of the word (she doesn't enjoy causing others pain), but she sure enjoys teasing Carter. She calls him "chicken man" among other things, noting: "I couldn't completely stop teasing him. I have a reputation to maintain" (23.92). Or take this exchange, for example:
"She's hiding something," Carter said.
"Work that out for yourself, did you?" I asked.
He looked away, and immediately I felt bad. (19.115-117)
Sarcasm is one of Sadie's trademarks, and many a character remarks on her sharp tongue. Her father says she's "[f]iercer than Ammit" (41.58), and Anubis says, "I've learned to fear that sharp tongue" (41.59). Coming from gods, we're not sure if that's a compliment or not.
She might not admit it, but family relationships are kind of a big deal to Sadie. She misses her mom, and she reflects on their similarities and differences: "People always say I look like her, but I couldn't even get the spot off my chin much less look so mature and beautiful" (3.28). Because she inherited her mom's fair coloring, Sadie always gets angry when people assume that Carter and her dad aren't related to her.
Not that her relationship with her dad is perfect. The fact that her dad took Carter instead of her after their mom's death has always hurt her: "Dad had practically abandoned me at age six, after all" (3.19). When Sadie does finally confront Julius inside the red pyramid, she says about her mother's death: "Isis should've helped her. You should've helped her. I hate you!" (39.66). Abandonment issues + blaming your dad for your mom's death + teenage hormones = a pretty potent mix of teenage angst.
Even before Sadie knew she was hosting Isis, she was pretty clever. When Sadie and Carter needed to break into Amos's forbidden magic library, Sadie thought ahead and snagged some Cheerios to distract Khufu.
Let's be real: Sadie needs all the smarts she can get, because she's behind the curve when it comes to ancient Egyptian knowledge. She never paid much attention to her dad's line of work, and her attitude toward ruins and artifacts is that "once you've seen one pile of crumbly Egyptian stuff, you've seen them all" (16.92). Sadie learns to look beyond the surface, however, as soon as her life starts depending on it.
Eventually, Sadie's picking up things pretty quickly. Anubis tells her she's perceptive when she realizes that the Hall of Judgment overlaps with a New Orleans graveyard. She also puts two and two together and realizes that Zia is a shabti long before Carter does. Lucky Carter, having a sister as smart as Sadie.