[sansa refrains from mentioning that rhaenys, aegon, and visenya were all siblings. she also refrains from asking how he never managed to get an impression of sibling relationships secondhand. instead she nods.]

Yes, when a family's good, it is--the best friends anybody could ever have. Friends who love you better than anyone and would never, ever leave you if they could help it. When they tease you, you laugh, because...it only goes to show how well they know you. But when they're cruel, it wounds you, because you know they're meant to love you. And some families can be very cruel.

[she wasn't totally oblivious to the lannister family drama that had been unfolding around her in king's landing, but it's the cleganes she's thinking of here, for the most part.]