She goes to read her letters.

They inform her about things that various courts would be willing to trade for some lights, depending on how many lights she could do and how long they last. They include objects from their style of magic, stories, other information, and artwork. No one actually mentions prisoners.

...anything neat in the magic objects department?

Magnifying crystals, heating stones, slowing stones, miscellaneous ones with fewer established practical uses.

...she goes looking for his father's son.

In his rooms, writing.

She's not sure how to politely interrupt, or if there is such a thing. She waits a bit.

"Plainspeaker!"

"Hi! I have been offered a lot of stuff and I don't know if I even want any of the stuff and some of it is magic."

"Personally I always want magic stuff."

"That's why I figured you'd know about what the stuff is like and what I could do with it."

"Do you have a list?"

She has brought her letters; she reads the offers of magic stuff off.

"Huh. Well, I'd take most of those, if it's less than a month of work; magic items take so much longer than that. But the most useful ones are..." and he draws up a list for her.

"What are they useful for?"

"Experiments, observations - lots of things change their properties really interestingly when they're hot - slowing people, obviously, for the slowing stones - I think iron-friendliness is important for things other than toys but I admit I haven't yet figured out what -"

"What's slowing people good for?"

"Mostly so they can do our magic, or have children. You can also do it if you want to not have to deal with someone for a while? If the person you're entangled were here, say, and didn't get along with anyone, I bet my brother'd have tried slowing her for a couple of days."

"And she wouldn't be, like, especially likely to get into trouble in those couple of days?"

"Mostly it's not a good idea to wander slowed? Most people don't speak the mortal languages and can't really settle in with them."

"Sure, but what would she do instead?"

"Magic, if she can do any? Draw pictures and watch animals move, if not?"

"I guess. Is the situation of not getting along with anyone generally resolved after that long?"

"Sometimes? Sometimes when people really hate each other they just need to go a long time without having to interact - or having to avoid it - and then they can tolerate each other. Sometimes by then one of them has changed a lot. Some kinds of entanglement lessen over time, though names don't until you forget them."

"I have reason to believe mine with her does not."