hi chels! I AM INCREDIBLY EXCITED FOR THIS -- i think, considering siobhan is so close to her sister, she would probably not be that fond of rowan given that it seems he's made a minimal effort to get to know treassa? & siobhan sort of lives in a world made of roses and posies, where her own arranged marriage has, for the most part, worked out, so while she is tolerant and occasionally tries to appeal towards rowan to be, you know, more of a ~presence~ in terms of being a husband & brother-in-law, she might be more resentful/annoyed and this probably manifests occasionally despite her groomed, uh, learning.
yes! i figured not everyone can be a heroic rebel, so i decided to throw in the necessary peter pettigrew. i'm sure when rowan and gregor interact, it will be interesting -- gregor has experience dealing with rebellious royals, since he is the primary contact for the s/c princess.