Ketheryna looks shocked and more than a little woozy, so you help her to a stool by the window.
"Oh, thank you. I just don't... that is, he mustn't... if... but... oh!" she says, and bursts into tears. Abandoning the final stage of the ritual for now, the three of you try to make her comfortable and eventually, through tears and explanations that begin at the end, and meander through diversions to the beginning, you work out the story.
In Ussura, the Kniases of the provinces are generally chosen by heredity, but the position of the Gaius is chosen directly by Matushka, often from the peasantry. When the old Gaius dies, Matushka chooses a young man to be the next Gaius, whose hair turns bright white, and who receives the great white Snow Tiger spirit skin. However, when Ilya was born to the previous Gaius Nikolai, Nikolai tricked Matushka into granting him any gift within her power to give--and requested that Ilya be Gaius when he died. She was furious, but could not go back on her word. Years later, when Nikolai was killed by treachery, Ilya's hair turned white--and he knew his father was dead.
Ketheryn is a bundle of conflicting emotions. She's happy that she's pregnant. She's sad that her child will not become the Gaius. And she's dreadfully afraid that Ilya will want for his child what Nikolai wanted for Ilya, and that he'll anger Matushka by demanding it. Add to this the stress of the war, and, well, it's a good thing she has friends like the three of you.