In which Justin Massey's wagging tongue changes everything
"One more petitioner," Vardis Egan said quietly. "Shall I admit him?
Jon Arryn suppressed a sigh. If he allowed himself to sigh every time he wanted to, he would long have been a broken man. Weight seemed to press down on his shoulders even as the blades of the Iron Throne pressed against his back and arms. The weight of a kingdom, the weight of being Hand for an absentee king, the weight of all the deadly secrets he had recently uncovered.
Robert had no legitimate children. The Lannister marriage that Jon had arranged for his onetime ward—had the warding really ever ended?—seemed to mock him every time he passed by the three children. Gold of hair, green of eye. Not black of hair, blue of eye.
He would have to tell Robert soon. He had the bastards Gendry and Barra, he had the book with the crucial passages. There would be no containing Robert's fury when he heard the truth, but Jon wanted to take no chances of word reaching Cersei. Blood would almost certainly be spilt, and far better that it be Lannister blood than Robert's. Of either of his sons.
On the morrow, the younger Robert would be on a ship bound for Dragonstone. Lord Stannis said that one of his trusted men, somebody whom the Master of Ships used for some of the more unsavory business that Jon assiduously avoided knowing the truth about, would be ready with a small but fast merchant ship to collect the boy. Maester Coleman had been told to prepare the boy's things by the next week; the baggage would indeed go the next week, but it would follow Robert, not accompany him. By evening the boy would be with Stannis, and Lysa would be on her way back to the Eyrie. And once he was sure that they were safe, Jon would tell the King everything.
Jon would do right by all his sons, Robert and Ned and his own Robert. It would be good for the boy to be away from his mother, and in a place where he could be properly taught to be a man. Stannis would not be able to spend much time with the boy, but Maester Cressen would be a far better teacher than Pycelle or Coleman. As for training with arms, one simply did not walk down a corridor in Dragonstone without running into a scarred man of some sort. Perhaps in time a betrothal could even be arranged with Stannis' daughter Shireen. If she was like her father, Robert would have a strong hand to help guide him, while Shireen would have a far better home in the Eyrie than what Stannis called "that pile of rocks." Then when Robert and Jon and Stannis were all gone, hopefully many years hence, the rightful ruler of Westeros would have the support of the Vale. The support and hopefully the love of his young boy, the last of House Arryn. A love that he had never been able to give to Lysa.
Could Dragonstone make Sweetrobin a strong, wise man? All those wasted years for his son…if only he could have spent more time with the boy, Jon thought briefly. But it was too late to dwell on regrets. He had placed the kingdom above the boy, and failed both. Yet there was still time to set things straight.
The hardest part would be to tell his wife. It would have been safer to tell her after the fact; Lysa would be furious, he knew, and might have to be separated from the boy by force, which could alert the Lannisters. Lysa and he had never loved each other, but Jon genuinely wanted to do right by her. So he would have to tell her. They would lunch together that day, and then break their fasts in the morning together as well. Better to tell her in the morrow. It would be one fewer night of pain for everybody.
"My lord?" Vardis' stolid voice was laced with a tinge of concern for his liege. "Should I admit him?"
Jon roused himself from his thoughts. "Who is it?"
"Ser Justin Massey. He has Lord Stannis' confidence, or at least that's what he says."
"If he's one of Stannis' men, it shouldn't take long. Send him in."
By the time Justin Massey was done talking, Jon Arryn found himself wondering how Stannis could possibly stand having this man serve him. Justin was a member of the ancient but poor House Massey, and as a younger son he would inherit close to nothing. But the lord of an estate bordering Stonedance had recently died without children, and Justin wanted that land. The law was clear enough; the lord had cousins, and it should go to them. However, Justin waxed eloquent, and it was an hour before the audience was over. Jon Arryn had to call the squire Hugh over halfway through and instructed him to tell Lysa that he would miss lunch.
The tears fell the next morning. Lysa had turned pale when he told her that her Sweetrobin would be taken away soon, then burst into tears, then began trying to alternately cajole and threaten him. He felt like a monster when a sleepy Robert was brought in to say farewell, and Lysa had to be physically pulled away from her son. Jon Arryn wondered for a second how he would have reacted if forced to surrender Ned and Robert, sixteen years earlier, before banishing the treacherous thoughts. This action, no matter how much it hurt, would be for the best for everybody.
A carriage was waiting in a courtyard. Jon would sometimes take Robert for a ride around King's Landing; that day, he would be unable to do so, so Ser Vardis Egan would take his place. In an alley that was hopefully discreet enough, they would transfer to another carriage that this Ser Davos would have waiting.
"My place is with you," Ser Vardis had protested, when Jon informed him of his new duties that morning. He, Lord Baelish, and Maester Coleman were the only ones of Jon's men who knew something of the Queen's Matter.
But Lysa trusted Ser Vardis, so she would know that Robert had somebody to protect him. He owed her at least that much. Also, it would allow Robert to have at least one familiar face with him. "I have enough men to protect me from the Lannisters," Jon told the knight. Besides, Lord Baelish had promised that the City Guard would be on his side. At least some of the Kingsguard, as well. He could count on Ser Barristan, Ser Arys, and Ser Mandon, and hopefully the rest—besides the Kingslayer, of course—would stand behind their king.
"Protect my son," he told Ser Vardis at the end. "When you arrive safely in Dragonstone, send a raven. Say that the falcon has landed."
The boy was a far more difficult farewell. He was sullen, and Jon feared that he might break into one of his shaking fits before reaching the shelter of Dragonstone. In the end, Jon simply patted him on the head. The boy would accept no gentle words, and did not so much as look at his father as he got into the carriage.
Jon Arryn felt tired, so very tired, as he watched the carriage disappear and took a last look at Lysa sobbing in the window. I could not do right by my wife, the Hand thought, but at least I have done right by my sons. And his heart felt a little lighter as he turned back towards the Red Keep.
So the point of divergence is that Jon Arryn is poisoned two meals later, too late to prevent Sweetrobin from being sent away to foster on Dragonstone. While the timeline of Jon Arryn's last days isn't clear from canon, I think that things would have moved very quickly to try to prevent the Lannisters from acting first, so I don't think it's implausible.