The Doctor did not know what to do.
Over the years he'd been in thousands upon thousands of situations that had seemed hopeless or futile or out of his control, and while he didn't relish the feeling, he knew precisely what to expect, how to manage the adrenaline and fear and anxiety. In situations like that, he knew how to not know what to do.
This – this was something entirely different.
There was no danger, no adrenaline, no lives or civilizations or planets or universes hanging in the balance. It was a calm, friendly, well-intentioned affair – simple and happy and human – and he had no idea how to deal with it.
Birthdays on Gallifrey had gone unmarked, probably because when one was anticipating a few thousand of them, the whole ordeal became rather redundant. Time Lords simply didn't do birthdays. They'd have found the idea of birthday parties – let alone surprise birthday parties -- with cake and ice cream and balloons simply preposterous, though he did suppose they might approve of the funny hats.
Birthday parties, surprise or otherwise, were yet another item on the list of human rituals the Doctor knew of, even understood, in an academic, removed sort of way. The past year had reminded him time and again, in ways alternatively subtle and blunt, that this encyclopedic knowledge was, for the most part, completely and utterly useless when it came to the daunting task of fitting in.
The Doctor was very good at many things. Fitting in had never been one of them.
So he stood, awkwardly, hands in his pockets and a ridiculous hat on his head. They stuck candles in the cake and they sang a version of Happy Birthday that felt foreign even still and the Doctor, for all his adaptability, couldn't help but marvel at how strange the situation was. Strange that there were hats and cake and songs to celebrate nothing beyond the fact that something had happened a year ago. Strangest of all was the knowledge that they'd done this, decorating and planning and singing, for him.
Once the cake had been distributed on plates far more expensive than plates really had any right to be, the Doctor found himself moving across the room to Donna. She'd been peculiarly quiet, aside from the singing, and there was usually only one reason that Donna Noble was quiet.
She looked up from her cake as he approached, the expression on her face uncomfortably familiar. He knew it backwards and forwards, on her face and all of his own, recognized it instantly the way he recognized himself in the mirror.
It was pity – pity and sadness and grief for someone else's loss, hidden behind a fake supporting smile.
He hadn't been on the receiving end of that look from Donna in over a year.
Rose stabbed at her cake with her fork, half-listening to the conversation her father was having with Jake and focusing a majority of her attention on the Doctor and Donna. Though she hoped the chance to steal the Doctor away and give him a heads up would show up on its own time, she rather doubted it.
"Something wrong?" she heard the Doctor ask, and from the corner of her eye she saw Donna's red hair bounce as the woman shook her head.
"'Course not," said Donna, evasively forking a piece of cake into her mouth. "So tell me, Johnny, d'you frequently forget your own birthday?"
Rose smiled down at her cake as she scraped the icing off her plate. "Johnny" was the only name besides "Doctor" that the part-Time Lord responded to with any consistency – "John" frequently met blank stares or delayed reactions, and "Dr. Noble" seemed to work solely because it contained the word "doctor". Like most nicknames, it was a moniker the Doctor had fervently objected to, and each objection had only seemed to cement its place in Donna's vernacular.
It was a name Rose had used it once, experimentally; the look that he had given her had told her in no uncertain terms that it was a name reserved for Donna. Rose didn't mind – it felt strange to call him anything but "Doctor", regardless, and the idea that the two of them got on well enough to have exclusive nicknames filled her with a maternal sort of glee.
Though she would deny it if asked, Rose had been worried when they'd run into this world's Donna Noble. Discouraging the friendship had not been an option, so she'd watched, anxious, and prayed that her Doctor was not disappointed. Rose knew too well how it felt to be shunned by a too-familiar face.
So far, he hadn't been – the Donna of this universe was brilliant in her own right, clever and funny and good in a crisis. Still, there were some sizable secrets between them – one of which, Rose supposed, she really ought to try and fix.
"Doctor," she said suddenly, walking over to the pair and sending them both a smile, "Mum put in some new carpet in my old room, want to go see?"
The Doctor stared at her. "Well… not really, no."
Rose was fairly proud that she managed not to roll her eyes. "Yes you do. Come on." She grabbed him by the elbow and tugged him towards the hallway. "'Scuse us, Donna."
The Doctor tagged along, looking perplexed as Rose lead him down the hall. "I'm sure the carpets are lovely, Rose, but—"
Deciding they were far enough from the rest of the party, Rose stopped and spun around, sending him an exasperated stare. "When are you going to learn to take a hint?"
He raised his eyebrows. "When are you going to start giving better hints? You can't expect me to feign interest in a carpet, of all things."
"Donna probably just thinks I feel like snogging you senseless," Rose reasoned.
The Doctor's look turned hopeful. "Oh?"
"Mmm. But that's not why we're here." She ignored his crestfallen look and carried on. "We're here because I … maybe sort-of…" She hesitated, rocking back on her heels a little. God, she was turning into him. "Well, I sort of told her your whole family died in a house fire when you were twenty-one."
It seemed to take a full second for the Doctor to register what she'd just said. Then his eyes did accurate impressions of dinner plates. "What?"
"I'm sorry! It's just – she asked, and I didn't know what to say, we'd never talked about it – why didn't we ever talk about it? – and I thought… well, it was the first thing I came up with."
She attempted to smile without cringing and failed. It had not really been her best moment, when it came to on-the-spot storytelling.
"A house fire is the first thing you thought of?" He was still staring at her as though she was insane, which was a bit rich, really, coming from him. He scratched the back of his head with one hand. "Well, that's a bit… traumatic."
Really, she thought, it was about as traumatic than the truth, but she was hardly about to tell him that. She shrugged. "More traumatic it is, less likely someone is to ask about it."
The Doctor regarded her skeptically. "You don't know Donna Noble." He sighed. "A house fire, Rose, really?"
"I'm sorry! I didn't have a lot of time to think about it!" she said again, raising her palms in surrender. Rubbing her eyes, she added, grudgingly, "you were in school at the time. And you had a little sister, sixteen." She paused, bit her lip, and concentrated on a chip in her nail polish. "Named Martha."
"Named – Rose!" he practically yelped.
"I know! It just… happened!"
"How does that just happen?"
"I don't know, I had to pull this tragic back story out of thin air and that's what came out!" She ran her hands through her hair and smiled apologetically. "It doesn't matter anyway, because you can tell her the truth."
The Doctor's expression shifted from a mystified brand of annoyed to closed-off in a split second. Rose was nearly impressed.
"I can't tell her the truth," he snapped, with the attitude of someone who has made the same argument a thousand times. "She—"
"Can't handle the truth?" Rose suggested wryly.
The Doctor glared. "The truth is insane, Rose. She's going to think I'm insane."
Rose shrugged. "Give her some credit, Doctor, she's seen some pretty insane things these last few months and it hasn't done her head in yet."
"That's – that's not even comparable," he insisted. "On the insanity scale that's a four. This is a twelve, maybe thirteen. Out of ten."
She snorted, which did nothing to dull his glare. "Come on, Doctor, it can't be that bad. Right now, she thinks you're an alien-obsessed, half-mad scientist with way too much pride in his doctorate who's just a teensy bit socially inept. Honestly, the truth is probably less strange than whatever explanation she's got in her head at the moment."
The Doctor stared at her with an expression that reminded her of blue eyes and stupid apes. "The explanation involving house fires and my sister Martha, you mean?" He let out a long sigh, his irritation transmuting into something that made her stomach coil in concern. "I can't tell her, Rose. That's not – I just – that's not how this works. She's friends with Dr. John Noble. The human. With… with house fires, apparently."
Rose smiled sympathetically, stepping forward to close the gap between them. She knew what he meant, and she knew that being anyone other than the Doctor. "That man doesn't exist," she said softly.
"He does," the Doctor insisted, staring over her head down the hallway. "For all intents and purposes, he does."
She bit her lip, tracing one hand around on his stomach, focusing on her fingers atop his shirt. "I know you're worried you'll lose her if you tell her the truth –"
"That's – that's not what I'm worried about."
"—and maybe you will." She drew a figure-eight with her index finger. "But you might not." She shrugged, lifting her gaze to his face. "Thing is, you will lose her if you keep hiding behind lies. She can't be your best friend if she's busy being John Noble's."
The Doctor said nothing; instead he looped his arms around her and pulled her closer, tucking her head under his chin. Rose lifted her head to press her lips to his jaw, then pulled away and took his hand. "Come on, we can worry about this later. Right now there's cake to eat."
Donna Noble did not know what to do.
She knew what she should do, in theory – she should probably pay more attention to the conversation Jackie was attempting to have with her. She should probably contribute something to the conversation herself, and she should probably not have another piece of cake.
Problem was, she couldn't stop thinking about what Rose had said, and as much as she knew she ought to bury it away, she couldn't. Jackie's description of new carpets did absolutely nothing to tear Donna's thoughts away from the one fact she couldn't seem to shake. The Doctor's family was dead, lost in one swift blow years and years ago. She couldn't imagine it.
To say he was eccentric would have been the understatement of the century – after all, he insisted on being called the Doctor. Occasionally he seemed so thoroughly perplexed by basic cultural customs that Donna had to question if his accent was genuine. He had an absolutely boundless fascination with sciences and aliens and space and things Donna had always associated with Star Trek. Put lightly, he was a little mad.
But he was also brilliant and funny and idiotically brave, and in the six months she'd known him Donna had grown fonder of him than she liked to admit. She hated tropes about kindred spirits, but the Doctor seemed to get her in a way that no one had before. Beyond that, he had an absolutely ludicrous amount of faith in her, for reasons completely unknown to Donna; he seemed to believe in her in a way no one ever had before, and she often worried that one day he'd realize how utterly misplaced that faith was.
The idea that perhaps his eccentricity – perhaps the way he talked and talked and talked without ever really saying anything at all – stemmed from something so horrible unnerved her. It made a sick sort of sense. She'd lost her father to the Cybermen years ago, an event that had shoved her out of the empty-headed rut of temping and telly that she'd found so comfortable. Was that what the Doctor had done, when he'd lost his whole world? Filled it with physics and aliens and ridiculous mathematics?
She couldn't imagine losing so much so young, couldn't imagine losing so much at all. She couldn't imagine coming out the other side of such a tragedy as anything but bitter and cruel and cold, yet the Doctor was none of those things. That amazed her more than any wealth of knowledge possibly could.
And so she did not know what to do. She knew that like most tragic tales of loss and woe it was probably not something that ought to be brought up at a surprise birthday party. She knew that the Doctor had probably never mentioned his family to her because even now it was a wound easily reopened. She knew that in many ways they were the same, and one of those ways was their reluctance to show any vulnerability.
She also knew that until she said something to him, her knowledge of his loss would stand in the corner of the room in the shape of a very large elephant, and Donna was never known for holding her tongue.
So once the Doctor re-entered the room (looking surprisingly un-snogged, she thought), Donna excused herself from Jackie and marched over to nudge him with her elbow.
"Oi, Johnny, can I talk to you?"