A/N: Set immediately after Journey's End. The Doctor takes a leaf out of Jack's book and goes back in time to get the chance to see Rose one last time.

Growing Up

There. That was the last of them. Donna was home. Not an hour ago, the Tardis had been chock full of his family. A fraction of those he'd had to leave behind before. Now, he'd said goodbye to them all again. Some for the last time. No matter how much he hoped differently. He stood suddenly. But he hadn't said goodbye. Not to them all. Not to the one his hearts said mattered most. He hadn't been able to. Without receiving orders from his large genius brain, his hands moved of their own accord across the console. The engines fluttered to life. The landing (he was flying alone again, after all) was harsh, but he hardly felt it. In a stupor, he stumbled through the door. What year was he? He couldn't remember. All he knew was he was somewhere near the Powell Estate.

Like a man dying of thirst, he stumbled across the square and crouched behind the dumpster. Waiting. Just waiting. Always waiting. Minutes. Maybe hours. Not days. He would have noticed a revolution or two of the sun and moon. At least he hoped so. He checked his watch. Four o'clock. Local time. On a school day. Any second. A laugh. Not hers. But familiar nonetheless. There. Jackie. Holding someone's hand. But-. Confusion invaded his features.

What was Jackie saying? "Honestly, Rose, if I get one more call from your teacher that you and Shareen been hidin' up in the tree house, I'm gonna have to switch you schools."

Rose looked grim. Around seven or eight, he realized. She was so young, so different but exactly the same. This, he realized when Jackie looked away. The corners of Rose's lips had been drooping, but now, as Jackie turned, she gave her signature smile, tongue caught in her teeth mischievously. Oh yes, his Rose. The one and only.

His chest constricted.

Her eyes sparkled.

He backed up to the wall, his hands clenched in fists.

She rolled her eyes jokingly as her mother continued complaining.

But he didn't hear her words. Because all he saw was her. She had so much left to do. For the moment, though, she was gone.

He sprinted back to the Tardis. Flipped the controls. Minutes later, he was out the doors again and sprinting back to his dumpster. This good old dumpster. He must have passed it a hundred times before. Never given it an ounce of thought before. Never realized how important it would become. Not seconds passed and a 14 year old Rose turned the corner with Jackie in tow again. This time, he had the pleasant surprise of hearing her voice, almost identical to her 19 year old one.

"I keep tellin' ya, mum. Somefin' fishy is up with that man. I know you said it wasn' our place, but Shareen and I couldn' help but investigate."

Jackie clucked impatiently at her daughter. "Well, I did say it before, and I'll say it again. It ain' your place to go snoopin' around people's offices."

Rose just laughed. The Doctor found himself smiling widely. Rose Tyler. No, he'd never had to pick her. Though he did. The universe had picked her out specially for him. A perfect match. His smile faded. A perfect match still, only in a different universe. No, he refused to think about that.

Three of his own minutes later, he was back four years later. He waited at least an hour and a half this time. Two young giggling girls turned the corner. His breath caught to simply see her almost exactly as he'd left her, her eyes sparkling with laughter, not a line of trouble on her face.

The other girl, about the same age, looked remarkably like Martha but shorter, more graceful. "If your mum finds out we blew school again-." She was saying, but Rose shushed her, laughing.

"Keep it down, Shareen," she spoke between giggles.

"My mobile," the other girl exclaimed suddenly, clutching her pocket. She pulled out a phone and looked at the screen. "It's Mickey." She whispered loudly.

Rose burst into another fit of giggles. "Give it 'ere." She said, and the Doctor couldn't help but roll his eyes. Mickey the idiot, he thought fondly.

"Gonna finally give 'im another chance?" Shareen chuckled.

"We'll see," Rose answered mysteriously.

He painstakingly listened as they arranged to meet in less than an hour. He waited as the girls disappeared to change, then followed them discreetly across the square. It was imperative he not be seen. She wouldn't recognize him now. But reality was she'd never see him until that fateful day of life and death and regeneration.

As the two girls waited at an intersection, something nagged at his mind. Time slowed as the light turned. He saw what would happen, what he had to prevent. There was only one way, reality be damned.

"Rose!" She stopped midstep. As she turned, he crouched in a doorway, not sure if she'd seen him or not.

Moments later, a car sped impossibly fast around the corner. "Blimey!" Shareen's exclamation redirected Rose's attention.

He hurried away from his alcove, away from the scene. But he could have sworn he'd seen her in the reflection of a car window, staring back, searching for him. For a split second, their eyes met in the reflection. Then he was gone.

In another universe, Rose woke with a start. Her heart pounded from the dream, more a memory. She stared at a familiar face, then silently slipped from the bed and floated to the window. She stared out at the blinking stars. That specific moment in her memory had been blotted out until just then. It all came back in a rush, but she remembered nothing as vividly as the sound of her name. And the face of the stranger. Everyday, out in public, the average person saw at least a thousand different faces. You never remembered the face of a stranger. Unless you got to see that face again, everyday, came to love it, came to hate seeing it sad or frowning.

She looked behind her. Yes, that face. The one she woke to each morning. Except- She turned away. It was an identical face down to the last freckle, but a different one. She shivered and crossed her arms across her chest as she focused on one twinkling star. Inexplicably, a smile invaded her features and tears sprung to her eyes. Somewhere far across reality, universes away, he was watching over her. It had already happened for her and for that she was grateful. But while that was true, she took comfort and joy and pain and sorrow in the knowledge that he'd never forget her. She only hoped he realized she'd never forget him either. And not just because she was married to his clone. No. She didn't mean his image. Or the idea of him. She meant him.

On the roof of the Powell Estate, the Doctor sat back on his hands, his legs dangling as he looked up at one twinkling star that had caught his attention. He'd go investigate later. But for the moment, he felt content. Because even though he could never go back to her as he knew her, she was alive and happy. And he was only too glad to have contributed to that. He thought back to their last farewell, painful as it was, but he was smiling.

"But he's not you."

The Doctor's grin widened. No, he's not, he thought. And despite everything that had followed, despite having to leave her, he was so incredibly ecstatic to be able to go on knowing that she could never truly substitute anyone else for him, as he could not her. Irreplaceable, the two of them. And even though they couldn't be together as it should have been meant to be, he would have to be content knowing there was nothing, no two others, in reality quite like Rose Tyler and the Doctor. The Doctor and Rose.

A/N: Don't give me that about "impossible" to go back on personal lines. AU, remember? I can do what I want. Now review unless you wish to hear the beating of the drums for all eternity.