This story takes place in the same world as Out of Joint, and overlaps some of the events in that story. It isn't necessary to read that story to understand this one, but it will provide context for some of the early events in My Brother's Keeper.

Tony Tyler's first memory was of The Doctor. He was four years old, and he had been at a park with Rose and The Doctor. He was carrying a grape ice lolly, the kind that snaps in two. His sister had bought it from a street vendor nearby. The heat of the summer day was rapidly melting the icy treat, and he wasn't yet skilled at noticing such things. Plop! The ice lolly had fallen on the ground in a sticky smear and Tony was crying his eyes out. The Doctor leaned down and gave him the biggest smile he'd ever seen, or saw since. The manically grinning man whispered that they were about to have a bit of fun. Tony stopped crying long enough to look up and see what the Doctor had planned. The man reached into the pocket of his pinstriped suit, and pulled a magic wand out of his pocket. With a wink at Tony, he pointed it at the grassy area nearby. Instantly, all the sprinklers were running.

"Now," whispered the Doctor. "Let's run!" Together they ran hand in hand through the water. Tony laughed wildly, clutching the older man's hand tight with his little fingers. It seemed to him that nothing could ever be as good as that moment again.

In Kindergarten, Tony had come home crushed. Eager to impress his classmates, he had told them all about the dinosaur people who had lived so long ago and hibernated under the earth, waiting for a day when they could safely return. It was his favorite story that the Doctor told him, and the Doctor had assured him that every story he said was true. The other kids had jeered at him, teasing him until he was in tears.

The Doctor had found Tony sitting out by himself near the gazebo, pulling grass from the lawn and throwing it away from him in angry clumps.

"Hello, little Tyler," the Doctor said. "What seems to be the problem?"

Tony looked up at the Doctor, trying to blink away the tears. Pretending he hadn't been crying.

"Nothing. I'm fine."

The Doctor rocked on his heels, his hands shoved deep in his coat pockets. "Fine. Fine fine fine. A fine state to be in. Good thing you noticed that alien lawn was creeping up on the house. You've stopped it in its tracks. I never did trust ground cover. Almost as untrustworthy as the shrubbery."

Tony glared at the Doctor. "There's no such thing as dinosaur people!"

The Doctor looked startled. "Well now, who says that then?"

"The other kids in my class..."

"Yep," the Doctor nodded. "They'd know, wouldn't they? Traveled all of time and space, and seen everything? They could tell you about the Silurians, the Raxicorfallipatorians, or the Grand Bazaar of Eginahmet. I bet they could build a hyperphase resonator too."

Tony blushed. "No..."

"So maybe, just maybe, your classmates don't know everything, do they?"

Tony remained silent.

"Do you think I know everything?" the Doctor asked quietly.

Tony stared at him with wide eyes, considering the question. Slowly, he nodded.

The Doctor gave him a huge grin. "Nah, not me! Or anyone! And that, Tony Tyler, is what is so beautiful about the universe. There is always more to learn, always more to see, always more to know. For your classmates, for you, for me."

The Doctor reached into his pocket and pulled out a piece of hardened leathery material.

"What's that?"

"A piece off a Silurian's armor. Picked it up as, well, a souvenir I suppose, a long time ago."

Tony looked at the ridged plate with curiosity written across his face.

"But I suppose I don't have much use for it now. Takes up space. Probably should just get rid of it." He tossed the dark object from one hand to another. "Unless... Well, I don't suppose you would want it?"

Tony nodded solemnly and the Doctor grinned and dropped it in his hand.

"Thanks," Tony whispered, turning it over and over. That night, he carefully put it on the shelf above his desk, a space he had saved exclusively for the little gifts and souvenirs the Doctor presented him with. "There's always more to know," he repeated.

"Watch where you're going then, Tony!" snapped Jackie Tyler, as he pushed past her on the stairs, heading down them three at a time. "Where's the fire?" she called after him.

Tony didn't answer her; there was no time. He leaped the stairs as madly as only a seven and a half year old on a mission could manage. The mail had come, Tony knew. He had seen the postman drive by in his van. And the mail meant one thing – the chance of a postcard from Rose and the Doctor.

He ran at top speed across the large front lawn towards the gate. He approached the mailbox that was built into the large stone wall and could be opened from either side. Enough of the media had bothered his family that they kept their mail secured at all times. But from the inside of the gate, it was easy to reach.

Tony pulled up the bundle and carried it to the house, going through it on the dining room table. Sure enough, sandwiched between a power bill and some sort of business letter for his dad, was the postcard. The picture on the card showed a man sitting on the ground in rolled up pants, and a brown shirt and hat, playing a whistle. He held a leash attached to an apathetic looking llama standing behind him.

Tony turned the card over. The writing was the Doctor's. Mostly the Doctor wrote, but sometimes Rose did. He peered at the tiny cursive. The Doctor always had so much to say, but seemed to enjoy the challenge of cramming it all onto a single postcard.

Hello Tony! Greetings from Cusco, Peru! This used to be an Incan capital. They built the city in the shape of a puma! Imagine, animal based architecture! Rose found some little shops to explore, so I decided to take a detour to a hill called the Temple of the Moon. Turns out the Incans believed in three planes: the Heavens, Earth and the Underworld. This temple may have been a means of communicating between the Silurians in the 'Underworld' and a bird-like race from Artan VII in the 'Heavens'... Well, it was all a bit of a confusing mess, but we got it sorted out. Rose may have had to collapse a tunnel entrance to block some of the bird people, but let's not tell the Peruvian government that, hmm? Can't wait to see you at Christmas, little Tyler! -The Doctor

Tony carried the postcard back up to his room, pulled out the large shoebox from under his bed, and slipped it on top of the ever growing stack of postcards within. He missed both the Doctor and Rose. They had been traveling the world for the past two years, and every week without fail, he'd been sent a postcard recounting their adventures. Tony wanted more than anything to be like the Doctor when he grew up. The adventures of the Doctor and Rose were amazing, and he had already begun to feel confined by the routine of the house and school. He didn't have many friends at school, and no close ones. Anyone he'd grown close enough with to share his love of the unusual and exciting stories had laughed or simply not believed them. It was disheartening.

Sometimes the Doctor and Rose flew home. For important days, mostly, like his birthday, Christmas, that sort of thing. He'd noticed lately that the Doctor was changing. He looked older and more tired. Anytime he'd tried to bring it up with either of them, the Doctor would distract him with a tale of a wild adventure, and Rose would frown, look distracted, and change the subject. He thought maybe they needed a vacation from their travels.

Tony sat on his bed, hugging his knees. He felt terrible. Sick, scared and miserable. Two weeks ago, Rose and the Doctor had flown home for the first time in six months. He had wanted to go to the airport to meet them. He always went to the airport to meet them. But this time, his dad had given him a strange, sympathetic look then told him that he couldn't come.

While his father was gone at the airport, his mum had sat him down on the couch. He could tell she had something upsetting to tell him by the way she seemed uncharacteristically quiet.

"Sweetheart, I've news for you, and it isn't good," she had said. "The Doctor... Something's wrong with him. He's been getting older and now he's sick."

His eyes widened. "But they can help him, right? He can go to hospital and the doctors will fix him."

Jackie sighed and ran her hand through his hair. "Sometimes there are things that can't be fixed. Just be there for your sister, all right? She'll need us to be strong for her. Do you think you can do that?"

He had nodded solemnly. When Dad came home in the black Lexus, Rose had climbed out first then gone to the back passenger door and opened it. She'd reached inside, and helped the Doctor out. Tony had stared. The Doctor was transformed. He had been looking older before, but now he was positively ancient. His hair had turned completely white and thinned considerably. His limbs were skinny and bent awkwardly. Every move the Doctor made was difficult and deliberate. And his face... Lines of age criss-crossed every surface of his skin. It was impossible to imagine him as the young vibrant man he had been just three years earlier. The Doctor had looked up and smiled at Tony. It was the same smile he had always had, so full of vibrant optimism. Tony turned and fled.

The Doctor and Rose had stayed at the house for three days. Tony tried to avoid them as much as possible. At first, he had tried just staying in his room and pretending to be sick, but finally Jackie had stormed in and ordered him downstairs in a tone of voice that brooked no argument. So he had come down for meals as necessary, and stared at his plate. The Doctor had tried talking to him a couple of times, but Tony would answer monosyllabically and look at him as little as possible. Eventually, the Doctor would be overcome by coughing or a fit of fatigue, and everyone's attention would move away from Tony again.

On the third day, Rose had come into his room, where he sat playing a game on his game console. He didn't look up, and she said nothing, but sat down next to him on his bed. The colorful characters careened around the screen, and Tony jabbed the controller violently, trying to crush some cartoonish enemies with a particularly erratic move.

Rose bumped his shoulder. "Everythin' all right, Ton'?"

Tony shrugged, and continued to play his game.

"You've been pretty quiet since we got back." Rose looked over at him. He didn't respond, his eyes glued to the television. She frowned thoughtfully.

"It hurts me too, Ton', seein' him like this." She saw Tony's eyes flicker towards her, but he remained silent. "The Doctor and I, well, I think I loved him since the day I met him. He has that effect on people, doesn't he?" She smiled.

Tony nodded.

"I... We... We're going to lose him, Ton'. I thought he'd find a way to get better, but I guess..." Her voice broke. He put down his controller and turned to look at her. Rose's eyes had filled with tears, and he saw that she was barely holding it together. She suddenly pulled him in for a hug, and he didn't resist. As she wept into his hair, his own eyes betrayed him with the hot sting of tears.

When at last Rose released him, he said softly, "It's not fair."

"Yeah," she said. "You're right. Of all the people… no, it's not fair." She didn't seem to have more to say, and soon he picked up his controller again, and went back to playing, while Rose silently watched the characters flicker on the television.

The next morning, the Doctor was in hospital. Tony was left at home with his father, Jackie having elected to accompany Rose. He didn't understand why he and his dad weren't there too.

"We will be, son," Pete finally said. "But your mum and Rose, they have… well, he's very special to them."

Tony had scowled. The Doctor was very special to him. He realized that his father didn't understand the connection he and the Doctor had formed over the years. Tony couldn't imagine growing up to become his father; it was only the Doctor that he dreamed of being. But it wouldn't help to argue about it now.

Several hours later, Pete led him to a car, and it was their turn. The hospital was an alien place to Tony, with its cold sterile hallways, and strange machines. It twisted his stomach to imagine the Doctor, so curious and full of life, in such a hollow place. They had taken an elevator and several corridors, and then they were at the Doctor's room.

Jackie was outside the room. "Just givin' them a bit of privacy. But he's been asking after you, Tony." She bent down to be level with his face. "He's dyin', sweetheart. It's a hard thing to see. But he'd like to see you, so try to be brave." She kissed the top of his head and straightened.

Tony took a deep breath, and stepped into the hospital room. The lights were dimmed a little. A television was mounted high on the wall, but it had been left off. There was a single bed, and in it, the Doctor's form rested. He seemed to be shriveling into himself, Tony thought. Soon there wouldn't be anything left.

Rose sat next to the bed, and she was holding his hand. She looked sad and angry and trying to suppress all these things. She just stroked the back of his hand with her thumb and stared into his eyes. Tony scuffed his feet a little, feeling awkward at his intrusion on such an intimate scene.

She looked up at him, startled, and the Doctor's eyes weakly focused on him. Getting up, she walked over to him, then told him in a hushed voice, "He'd like a few minutes with you, Ton'. To say goodbye. Just come out when you're done, okay?" Rose gave him a tight hug and left the room.

Tony stood, and stared at the ghost of a man on the bed.

"Now, now, little Tyler," said a faint version of the voice he remembered. "No waiting around. For a Time Lord, I seem to be strangely short on time, so we'll have to make the best of what I have."

Tony shuffled closer, and sat down on the chair Rose had left. The Doctor turned and stared into Tony's eyes. He couldn't help but think that the expression in those eyes was the only thing left of the Doctor he remembered.

"I'm sorry I won't be around to see you grow up, Tony," he said. "I had another brother, once upon a time. An older one. I've tried not to make the mistakes he did, you see. It's been wonderful. I didn't think I'd have a family again, not after everything…" He stopped and coughed weakly for a minute, then sighed. "Well, it's been nice to have one."

Tony nodded. He didn't trust himself to speak. The tears were hiding just behind his eyes, and any false movement would cause them to flow. He wasn't sure he'd be able to stop them if they did.

"I've got a couple gifts for you, Tony," the Doctor continued. He seemed unconcerned by Tony's silence. "One is sort of an ongoing gift. Really, a project I started a few years ago." A ghost of the Doctor's manic smile drifted across his face. "Think of it like the fairies' gifts to Cinderella. Well, just one fairy. Not that I am, in fact, magic. And I don't have wings. And you are definitely not Cinderella. I mean you've got the hair and eyes, but really, not the figure. Anyway… Tony Tyler, I grant you the gift of cleverness. Not that you wouldn't have been on your own, but, well, let's just say I greased the wheels a bit. Here, lean in, and I'll tell you."

Tony was curious by the sudden turn of conversation. He leaned in close to the Doctor and the Doctor turned just enough to press his forehead against Tony's.

Suddenly, Tony was assaulted by a blast of images. They whirled around his mind, and he felt dizzy and ready to pass out. Then, just as quickly as they came, they faded away. The boy reeled back from the Doctor, clutching his head.

The Doctor smiled sympathetically. "Sorry about that, Tony. I'm afraid I no longer have the time for subtlety." Tony was still recovering, but the Doctor continued, ignoring the younger Tyler's confused state. "That was part of the second gift…" Once again, the Doctor paused to cough, but this time it was long and wracking. Tony could hear a wet bubbling behind its harshness.

"The second gift," gasped the Doctor, who seemed grimly determined to finish. "You'll find that at home. Don't lose it. Well, really, you can't lose it. Impossible. Or at least highly unlikely. I added a mild telepathic impulse to keep you from misplacing it." He smiled again. His raised his hand from the bed weakly and Tony clasped it. "It was wonderful having a brother once again. And I know you will have whatever success in life you wish." He squeezed Tony's hand once, and sighed. "Now you'd better send Rose in. I don't think I have much left in me."

Tony nodded and stood. He fought back the tears, and took one long, last look at the Doctor. Then abruptly, he turned and left the room. As soon as he emerged, Rose barely glanced at him before she hurried into the room. Pete clasped his shoulder, and Jackie gave him a big hug. The tears spilled down his cheeks as his mother stroked his back and whispered meaningless soothing words into his ear. They weren't enough.

He waited on a bench outside the hospital room between his mother and father and stared at the clock on the wall ticking. An hour later, Rose emerged. Jackie took one look at her and wrapped her arms around her daughter, holding tight as the younger woman sobbed endlessly. Tony watched the scene dispassionately, and realized that he would have no idea how to act around Rose, now that the Doctor was gone. To him, they had been a unit. The Doctor and Rose. He never really remembered a time they hadn't been inseparable.

On the way home, Tony found himself silent and numb. Pete drove him to a small restaurant Tony had never seen before. They sat in a cheap red vinyl booth and he ordered a hamburger and a large chocolate milkshake. Not that he wanted them, but Pete seemed to expect him to do something of the sort and he didn't feel like making the effort to argue. He picked at the chips and barely tasted the milkshake. Instead, he looked out the window at the dark and rainy evening, and watched the raindrops race each other down the pane of glass.

After dinner, they drove back to the house, and on the way, Tony realized that what bothered him most was how much smaller and greyer everything seemed. It was as though the entire world was diminished without the Doctor in it. For the first time, he thought that perhaps it was a world he didn't want to be in.

Pete pulled the car smoothly into the garage, and Tony got out. He could tell his dad was concerned. There were far too many thoughtful looks, and no complaints when Tony allowed the door from the garage to the house to slam shut with a bang as he so often did. Tony politely excused himself, saying he felt like getting some sleep, and Pete had squeezed his shoulder again and said that they could talk in the morning. Tony couldn't imagine what Pete could possibly say then that would be helpful.

The stairs seemed endless now, and Tony trudged up them one by one, until he reached his room at the end of the hall. He pushed the door open, and kicked off his shoes and jacket, not bothering to turn on the light. Only once he was down to his superhero underwear did he click on the small table lamp next to his bed. And that's when he noticed the cube.

The cube was small and a featureless, a shiny black. It was about half again larger than the sort of dice you found in a board game box, and the corners were very slightly rounded. Tony stared at it. He was certain he had never seen it before in his life.

His curiosity managed to burn through the haze of depression and exhaustion, and he leaned forward to pick up the cube. As he brought it towards him for a better look, he felt it grow a little warm. Before he could drop it, a beam of light shot out from the top. Tony blinked at the sudden glare as the light quickly rearranged itself into the form of the Doctor. Not quite the Doctor, but a flickering projection about a foot tall emanating from the cube's surface.

The Doctor turned and grinned directly at Tony. "Well, hello! You didn't think I was gone, did you?"