"But… you could come with us," the Doctor says, and in some world she's strong enough to say no, not again. I can't do it again. Twice in one lifetime, no. That's too greedy. That's too much.

This is not that world.

*

"Still remember where your room is?" he asks, and she smiles. She feels giddy, light-headed and light on her feet on the metal grille, like the TARDIS is buoying her up, welcoming her home.

Home. Down the corridor, six turns to the left, past the gardens, second door on the right… "I think so, yes."

"We do all get different rooms, then?" Rose says. She's teasing and she's not, but it's mostly the first. It's going to be awkward for a while, Sarah thinks. But that's okay. That's all right. Awkward with the Doctor is nothing new.

"'Course," he says, grinning. "What, don't think there's enough room around here?"

"Oh, no. Never that."

"Come on, I wanna see your room," Rose says. She laughs but looks to the Doctor still, just to be sure.

"Go on, I've got work to do, stop getting in the way." He grins. Rose pouts. Sarah Jane catches him smiling when they're somehow hand in hand before reaching the door.

Her room is exactly as she left it, and at the door, she can barely breathe with the memories that come flooding back. Rose presses up against her, arm in arm and still holding her hand like she's afraid Sarah might step away and vanish.

"Go on then," she says and nudges harder. Sarah smiles and walks inside. Rose lets her go, leash let out now that it's real and she's in here, in her own room, her own space and time, the TARDIS. She wanders around the room and touches everything and everywhere memory wakes inside her.

When she turns to the bed, Rose is sprawled, watching her, with a grin just like the Doctor's.

*

She finds him bent over the remains of what may, once, have been mistaken for a slightly disco tin dog. She watches him for a long time until somehow her eyes slide away from his concentration and his quiet eyes and the way his hands move.

"Sarah Jane," he says softly. She looks up, back at him, realises he was only waiting. For her. That's new.

"Hello, Doctor."

"What's wrong?"

She sighs and shakes her head. There's no use hiding it, not from him. Amazing he doesn't know already. Maybe he does.

"Rose. I'm old enough to be her mother."

He brushes an ash-covered hand against his thigh, smudging black dust through the pinstripe. "And what does that make me? I'm old enough to have begat Jesus' uncle, or at least one of the later members of the family." He grins that broad grin of old, the one that should have given him away long before the blue box. "You humans, you're so caught up with your tiny lives. Wonderful. Like ants pretending that size matters. What difference do a few of your arbitrary years make?"

"You asked me to come with you again," she says, and the words say what she means even though they sound so simple.

"We both did," he says, softly, and wipes his hands better this time before taking her by both hands. "Rose likes you. You saw that little display of psychology." And he smiles at her, gentler than he ever did before. "She asked me if you could come."

"I know," she says. She hasn't asked, but he's right; she knew. She knows, too, that if he didn't want her here she wouldn't be here, and maybe she wouldn't even though he does, and this is the second chance she should have given up on expecting.

Her hands are trembling when she says, "Would you teach me again? How to… make it not matter?" She remembers now that silly things like this didn't, once, and she liked it much better that way.

He grins again. It tastes like crisp clean snow when he kisses her.

*

Rose whispers a name to her in the nightless dark inside the TARDIS. Jack.

Sarah Jane listens and holds her tight, her mouth still tasting of the Doctor. Rose isn't crying when their eyes finally meet, but when they kiss, she tastes of hot light and tears.

*

It makes it easier that they've done it all before. She's aware, of course, that the Doctor has done everything before, but Rose. Rose is nineteen. It's easier knowing that she knows what she's gotten into, too.

It makes it easier but not easy. It's been a long time, and Rose is young enough to make her nervous — nervous about the lines around her eyes, the hang of her breasts, the way her skin isn't soft and flawless as she imagines him remembering.

He tells her she's become more beautiful, and Rose asks if they ever took pictures, back then.

"Not of this," she says quickly, laughing. The Doctor shakes his head.

"Too busy seeing the universe to take pictures of it!"

She laughs. Her heart never doubted, but her mind is beginning to believe again, too. This is him. This is real. He touches her, and her body remembers. Rose watches her — them — and her mind wakes to forgetting; age and sex and separation, it all means nothing here. The Doctor and his companions, that's how it's always been. How it should be.

She sleeps holding Rose against her, the Doctor already grinning and gone. Someday soon she thinks he'll stay, but not yet. It's not… time.

*

The Madame de Pompadour fades from thought as she watches him sleep, Rose lying against him. She lays her head down against his bare shoulder and presses close, touching everywhere she can. His arm around her makes her warm, after what feels like far too long.

*

"I can't believe you're doing this," she hears Jackie yelling in the other room, and winces. The shrill voice of reason is an unwelcome intrusion on the life she's found again, all the more unpleasant for the newness of it. The Doctor never did family before. Now there's a mobile phone, an ex-boyfriend and a worried mother to consider, all weighed up against the adventure of a lifetime.

And Cybermen. She never thought she'd see them again. Never thought she'd be in this kind of position either, and she's not sure which is actually the more frightening. She makes tea in Rose's council flat kitchen while Rose throws clothes and CDs into a suitcase on the other side of the wall, and the Doctor tries to ignore himself pretending to reason with Jackie Tyler.

"We really do take care of her," she wants to say on her way out, but she stops herself just in time. From the look on Jackie's face, it's not at all what she wants to hear.

"Sorry 'bout all that," Rose mutters, hand in hers on the way down the steps. A pair of hoodie-wearing council estate teenagers give them a disgusted look and make signs as they walk past, signs that turn to wolf whistles and jeering when the Doctor puts an arm around them both.

*

The TARDIS door opens on a busy street under a teal-green sky and the sound of… pulse engines, she thinks. Hasn't heard them in a while, but they have a very distinctive thrum. Amazing, the things that come back to you.

"Welcome to the fifty-first century!" The Doctor grins at her expression. "Home of… flexible people, isn't that right, Rose?"

Rose looks up with dancing eyes and hugs him. "You bet."

She smiles. Then she laughs. Then she holds out her hand and lets them lead her out into the fifty-first century streets.

"Thought you could use a break somewhere with sunshine," is all he says when she asks. "Earth, I don't know. Doesn't have proper weather anywhere. Now this place, this is good weather. Fancy an ice cream?"

She knows what he means, and that the words are saying things he won't say, and takes his hand in hers while they walk.

*

From the fifty-first century to the nineteen-fifties is a shock to the system. She laughs at Rose in a pink taffeta skirt and remembers the one her cousin used to have just like it. She smiles at the Doctor on a moped and clings on behind him, Rose laughing at them both.

Once, she sees a police box on a distant street corner — old and disused, but just for a moment it makes her start. So long spent looking, for something just like that, that for a moment she almost feels tears.

The Doctor and Rose don't see it, ahead of her, imposter that it is — they're already racing the other way, hand in hand, and that alone makes her smile as she runs to catch up.

*

Black holes are a bad idea, and little children (on which they definitely do not plan), and monsters made up of far too many other people. The Void haunts her nightmares, when she has them, every one filled with cold steel and the sound of screams. She's forgotten once again what normal life is like, but she really doesn't care. This may not be normal life, but it is real.

They save the world, and it doesn't end. They give out happy endings, like Jackie and Pete together and Rose crying in her arms and clenching the flat keys into her palm. When it's all over they smile and say goodbyes again, and she wonders this time if they'll really be coming back.

The night after she tries idly to remember the way to her room, but it won't quite come. Six turns to the left, past the garden, but then Rose is sliding a hand across her stomach and she loses track.

"You're thinking," Rose says, admonishing her with that grin, the one that has her surrounded, as the Doctor nibbles a path with fascinated slowness down her neck. She laughs, pushes him out of the way to reach up and pull Rose down.

"Stop me then," she says, grinning back. The Doctor laughs.

"My Sarah Jane," he whispers as he moves inside her, and she feels Rose smiling into her mouth when they hear it. His fingers are twined with hers and his other hand with Rose's, and this time she believes, she truly believes, he isn't ever going to let go.

The Doctor and his companions: that's how it should be. That's how it is.

*