I recently finished a reread of The Perilous Gard and some things stood out that I wanted to note and see if anyone else wanted to weigh in on.
I noticed that the first time Kate and Christopher call each other by name is right after Christopher realizes Cecily is alive. All of a sudden, they’re on equal footing because Kate has brought this news to Christopher and it’s them vs. everyone else to rescue her. It’s lovely.
I love that Kate is the logical one and Christopher is the reactive one. And yet, Kate has the stronger faith. She is quicker to trust that there is more going on than meets the eye. Once she believes that Fairy Folk exist, she immediately sees the explanation for Cecily’s disappearance. Christopher, on the other hand, scorns the explanation until confronted with the proof of Cecily’s other shoe. Wherein he quickly leapfrogs his way into realizing he can offer himself for Cecily - and WILL be accepted as a much more suitable replacement. He recognizes that the Fairy Folk don’t necessarily think in a way that humans would consider logical.
Also, Kate obviously has emotions, but not only has she schooled herself to not show them easily, she also seems to genuinely miss or just ignore other people’s emotions sometimes. Whereas Christopher seems quite keen in this respect - he is the one who is very gentle with Randal when he’s confused, whereas Kate tries to correct him and has to learn to be gentle.
Also, how they fill in what the other most needs! Kate is willing to call Christopher out on his temper and she is willing to fight for him, to declare him worth saving (which isn’t to say his siblings didn’t, but Jennifer lives in London and seems rather distant with her own siblings, and Christopher has never gotten over Geoffrey’s going away and then the distance after Cecily’s disappearance), and to tell him his being born cursed is utter nonsense. Whereas Christopher, despite the rough start and the occasional negative remark (which quickly comes to be in the “how can you not see what is perfectly obvious to me” category) comes to love her, chooses her for herself, chooses her over Alicia (which is huge), doesn’t tell her she needs to change or is hopeless, and offers her a home. He also gives her a life-long job to do and place to belong, putting him to rights. XD
Also, don’t get me started on Christopher learning the tones of her voice just as much as she learned his! And how shocked Kate is by the realization that he knows her as well as she knows him, that - as much as it may’ve seemed like he wasn’t - he was clinging back to her as tightly as she was clinging to him.