[X] Since the Royces would have to agree to the story, you would prefer that they choose which story is the least onerous for them.
-[X] The simplest and most straightforward would be to fake Ysilla's death. A disease caught from foreign merchants, or an accident or something similar could be faked with magic, and then she be simply whisked away to SD. However, this would burden the Royces with having to pretend to mourn her, and would make her reintroduction more difficult, though not impossible. However, it should best shield from drawing suspicion to the House as a whole.
-[X] An alternative would be to have found that Ysilla was cursed, and sent to Braavos for curse breaking with a relative, like Robar. The Braavosi would "fail" and then Robar, rather than return home having failed, would leave Braavos last seen traveling further "East" in search of further solutions, but in truth being brought to SD to study magic for a year or two. This would allow for Ysilla's return, but would be likelier to draw suspicion. It would be easily explained as preferring the word of family, that is Waymar's, in recommending a curse-breaker in Braavos over rumor, but suspicious minds might wonder. The seeming failure of the recommended curse-breaker might deflect said suspicion, but you cannot say what other Lords might think.
-[X] If Lord Royce (or our companions) can think of an alternative that better provides a reason for Ysilla to leave home and travel outside the seven kingdoms, you'd welcome it, of course. You have been a bit removed from what is considered "normal" in Westeros, so you could be overlooking something.
, *to be fair, s/he does come up with insightful votes.
