One of those being Joy Hill.
When Tywin and Tyrion are discussing the aftermath of the Red Wedding, Tywin mentions that Joy's supposed to marry one of Walder Frey's bastards. A bastard wed to a bastard. Fast forward to Feast, and now it seems like Joy is supposed to marry one of the Westerling boys. Sybell remembers the phrasing as being that Tywin said "they would have joy of him," and it makes sense that yes, he did mean Joy Hill.
For one thing, if the Lannister-Westerling alliance was as well cemented as some people think (going so far as to suggest that Tywin rigged the marriage entirely), why was Joy first promised to one of Walder's bastards? That in and of itself suggests that the negotiations with the Westerlings came later, not earlier. Joy to Raynald or Rollam was not the original plan.
For another, as Sybell gracefully notes, it's an insult to the Westerlings for them to marry a bastard. If the Westerlings had really been "in on it" for a long time, and had actually given proper assistance in betraying Robb, why "reward" them with such a shoddy marriage? What if the "payment" for Joy was actually something that Tywin considered ... cheap? Remember that when Sybell explains the "plot" to Jaime, she does so 1. after Tywin is dead and he can't refute her and 2. knowing that Jaime is pretty ignorant of what the actual terms were. What if the Westerlings' real "betrayal" was making sure that Jeyne wouldn't have Robb's baby? You don't promise your bastard niece to a house that actually did you a valuable service. You do that if they're late to the party, didn't do that much in actuality and are only doing you a cursory favor.
Sybell suggests that it was Tywin's plan all along and that she gave Jeyne a contraceptive. But again, there's nothing but her word, and Tywin can't corroborate it. If Joy was considered a proper "reward," perhaps Tywin knew that the Westerlings' cooperation had never been solid, and it was a last-ditch effort to keep Jeyne from getting/staying pregnant and giving birth that earned them that marriage, not any real "betrayal" before the Red Wedding. Intuitively, helping out for a longer period of time should have been good for far more. Also note that if simply keeping Jeyne from having a baby was the later agreement, maybe even agreed to after the Red Wedding, Sybell did not need to have been giving Jeyne moon tea regularly to achieve that. See: Lysa and Hoster Tully.
Speaking of the Red Wedding. When Tywin explains the plot to Tyrion (where he mentions Joy's betrothal to a Frey bastard), he makes no mentions of the Westerlings at all. Later, when Tommen pardons some of Robb's bannermen, the Westerlings are mentioned, but only in passing. Nothing specific about their role is mentioned. The Westerlings lost one son at the Red Wedding and could very easily have lost another, if Robb had brought Rollam. The decision to leave Rollam behind appears to be one Robb made himself. It's not like the Westerlings asked for him to stay behind, and Rollam appeared to be upset over it. Yet these people were supposedly in on it from very early on? I don't buy it.
If they had been in league with Tywin early or from the beginning, why did they just not kill Robb (they could even lie to his men and say he died of his wounds) when he was at the Crag? (Kudos to Jarl the Climber for asking this first.) Tywin acts like the Red Wedding was necessary because it was otherwise nearly impossible to kill Robb. Yet the Westerlings had him in a very vulnerable position. The reward for killing Robb at that point would have been immense. But they didn't. Why? Because at that time, they were not in league with Tywin. When did they get in league with Tywin? I'd argue that it was actually much later than many people believe — not until after the Red Wedding, when they were pardoned and given the marriage option(s) in exchange for Jeyne never giving birth to Robb's child.
So why would Sybell put on for Jaime — who, again, would have been ignorant of any planning — and insinuate that their involvement was deeper than it really was?
1. By then Tywin was dead. Possible that Sybell hoped to get a better deal out of Jaime than she got out of his father, by inflating the Westerlings' role. For all we know, the "lords or heirs" thing was never promised at all, and Sybell's just grasping to see what she can get. Obviously that didn't work out that well.
2. If Jeyne had actually escaped by then (my theory), if Sybell laid it on thick that she'd been working with the Lannisters all along, it would give Jaime less of a reason to be skeptical of the girl in front of him.
3. Sybell wasn't actually "putting on" at all. She only says that Tywin asked her to make sure Jeyne didn't give birth, and people assume that this means that the "fertility potions" were actually moon tea. BUT, if this order came after the Red Wedding, that doesn't necessarily have to be the case. In that instance, it's just Sybell, who's an ambitious woman wanting to ingratiate herself to the victor, wanting more for preventing Jeyne's pregnancy than it should actually be worth.
The hangnail here is Rolph Spicer, Sybell's brother who was made Lord of Castamere. Grey Wind obviously didn't like him. I'd argue though that it's possible that he was doing something else in the Lannisters' service, or that he did something later (secure Martyn's release?) to warrant getting the lordship. For the Westerlings themselves, I only noted the marriages. Spicer got the real boon, and he's also not on the list of pardons with his sister's family.
Sorry for the long read, but I think there's a lot more going on here than meets the eye. The time line doesn't really add up to a long-term Westerling-Tywin deal, and neither does offering Joy in marriage after she was already promised to someone else. I think someone, probably Sybell, is lying or massaging the facts.
Edited by Apple Martini, 04 May 2012 - 01:59 PM.