All right... I'd quite lost track of this backwater of the timeline, and gotten lost in a morass of Henrys and Margarets. By snatching at some vague memories of previous scenes and doing some quick wikipediaeing I think I put it all together.
So this Margaret with Queen Cecily is not her daughter (does she have a daughter named Margaret? I know she has Alice, yes?) -- this is Lady Margaret Tudor. And so the boy is who, in OTL, would become Henry VII. And they both, I assume, are existing within the York/Black William households as hostages.
So Black William (reasonably) thought to place the hostage in a safer location, since he'd soon be having to deal with the boy's father in his own lands? I'm a little surprised he didn't hang onto him as an ace in the hole if he decided to switch sides again.
I enjoy the ongoing misstepping and confusion with regard to who is the Queen. Cecily, obviously, is NOT!.
I'm curious what Jasper might hope to gain. Or, more to point of fact, what he might actually gain, regardless of what he thinks or hopes. It seems badly timed, or perhaps just desperate.
Looking forward to more!
Rensslaer