Donna Noble, no hyphen anymore, is dying. She is very old (whenever she thinks that, something pings ever so quietly in the back of her mind), and she has done many things with her life (the ping again), and she is ready to die. Her youngest daughter, just elected the first female president of Mars (that ping once more), sits at her bedside, reading aloud from some trashy space romance. It's bloody awful: some immortal god comes to Earth and falls in love with a human, but he's not really a god; it's all rather confusing and besides there's no sex in it, which defeats the purpose of a romance, doesn't it, for Donna at least. And the author's a bloody terrible writer, really. But Donna doesn't mind the bad writing, not anymore, it's just nice to have someone here. The others — her children, grandchildren, her brand new great-grandson — are on a shuttle heading for Earth, their last visit over, all their goodbyes said. Alice, though, wanted to stay, and Donna's never been able to say "no" to Alice.
The room is lovely, sun-drenched and sparkling, the biodome's leafy canopy making everything look like a forest on Earth. Donna loves it here, loves the way she can sometimes trick her mind into thinking that Shaun's just popped out for a cup of tea, that Gramps is out looking up into the stars (a ping again, louder than before), that she's still young and full of life. The other people in the room, like her, are old and tired and dying, but somehow the sun makes everything feel clean and new. There's no stench of death, no sadness. Just old people in the sun, and young people by their sides.
One person, standing in the scant shadows across the dome, doesn't fit. He looks young enough, sure, a skinny slip of a man, with a bowtie and an odd face. Donna doesn't see him, but it wouldn't matter if she did — he looks like someone's grandson, popping out for a cigarette, or someone who's shy around death. If she could have seen his eyes, she might have wondered (his eyes looked older than anyone in this room's did, and sadder, too), but luckily for her she didn't see him at all.
As Donna Noble slips away, the man in the shadows does something he rarely does. He weeps, silently and only for a moment. Then he wipes his eyes and walks away, hands stuffed awkwardly into his pockets, bowtie slightly askance. If anyone had been listening, which they weren't, they would have heard him say something, softly, in a language that hasn't been spoken for hundreds of years. They wouldn't have understood the words, of course, but his pain and regret, his sorrow and sudden ache of loneliness, well, Old High Gallifreyan was always good at expressing those things.