In the end, it was nothing.
A moment of weakness, with all the blows that had fallen on him that evening, and with Jane so close, so generous, pale and dark-haired and knowing. A woman seeing him whole and asking, with her eyes wide open, to be with him. It would turn a saint's head and Robert was no saint.
Just a kiss, a moment of human contact. He tells himself he would have turned her away - kindly, with deep regret - in a moment more. He would have. He's not that kind of man.
But that was when Sybil threw the door open, her yell stopping on a dime.
Cora's saying, that. And Cora was burning, bleeding, but he only knew because he ran after Sybil, trying to catch her to explain, stop her from telling, stop her from ruining things.
He should have known better. They know how to keep secrets, his girls. Only their eyes turn hard and cold. Mary, first. Edith, at some point during the war. Now Sybil, as she reached over to close Cora's eyes.
Thirty years. A bad beginning, a happy middle, and now an end with the three girls cold-eyed strangers.
He came back to his bedroom in the small hours, shaken and cold. Jane slipped in soon afterwards, and her hands were warm.
Lavinia recovered, younger and stronger than his darling Cora. She took Matthew on a long walk around the estate. Robert watched them from an upstairs window, the way they walked hand in hand.
She took Mary on a walk next, and Robert kept watching. He should have kept an eye on Matthew instead, because Matthew took sir Richard behind the garage. Carlisle was never a man of honour, and that included a gun in his boot.
Cousin Isobel agreed that Matthew should be buried in the family plot. It was proper.
Edith was the first to leave, after the second funeral. Canada, somewhere in the middle of nowhere, where no-one knows she's Lady Edith and due all kinds of respect. She sounds happy, in her letters, and she's got suitors she writes about in a very small hand as if he could cross the ocean and smite them if he wanted to.
Mary writes to Robert sometimes, short notes of well wishes and no news of herself. He keeps track of where she and Lavinia move by their addresses, London and Berlin and Budapest and Belgrade. He plots them on a map against shots fired and governments overthrown. He wonders how he could think Downton was big enough to hold her.
Sybil hasn't spoken or written to him since that night. He doubts she knows that he has the birth announcement, written in a painstaking hand unused to calligraphy, from Branson's mother of all people. In another world, he thinks he could have found some common ground with that woman.
In another world, where the coin had fallen differently.