He remembers, vaguely, that human children do not develop a sense of mortality till the age of seven. This would most likely explain why a five-year-old Rose would think to cross the busiest intersection in all of London, entirely by herself. Though, she adamantly insists she is a "Big Girl" who can do such dangerous things without the aid of an adult, or even a reasonably responsible teenager. He's not entirely sure how she made it all the way here from the Estates, but he's set on bringing her back. This one just could not stay put, could she? Absolutely horrid with directions.

"You need to stay closer to home." The Doctor scolds, looking down on the tiny blond creature clutching his calloused hand. The little thing claimed she hadn't been scared in the slightest, but if her grip was any indication, the trip had been terrifying. Still, he wouldn't have guessed otherwise.

"S'no reason to stay." She shoots back. It's strange, hearing her voice so high-pitched any young. "Boring, that place. "

"Why would you go to Center London?"

The girl shuffles her feet, which are clad in pink, glittery trainers. "Mum is being silly."

"Silly?"

He couldn't quite make out the next bit, just a murmur of "makeup parties."

Now he understands. Rose had mentioned her mother's short career in the makeup industry a time or two. The Doctor nods understandingly. They did sound like complete and utter torture, to him at least. And it appears five-year-old Rose didn't appreciate them either. She huffily crossed her tiny arms.

They had stopped in the middle of the sidewalk and people were swerving around them. This received a steady mixture of glares, rolled eyes, and smiles. Clearly, the passers-by believed him to be a disgruntled father, attempting to reason with an equally disgruntled daughter. He turned to see that he had stopped directly in front of one of those poofy-dress stores. Please Mum London. He shuddered. She couldn't stand a make-up part, but a poofy-dress store?

"No thanks," He murmurs.

"Wot?" little Rose demands. "Wot is it?"

"Nothing." The Time Lord assures her. "We need to get you home, Rose. And soon. Your mum i'll be having a fit, I just know it."

"No she won't!" Rose insists.

He tugs on her tiny arm, propelling forward. "C'mon, Rose."

"No!" The girl pulled against his force, desperate. "I don't want to."

"Rose—"

"I don't want to go home."

The sight of her watering eyes stops him in his tracks. Sighing heavily, the Doctor rubs the back of his head. What to do, what to do…Rose, always stubborn. Typical. "Then what do you want to do?"

The hazel eyes, still welding with tears, peer around the street until they came to rest upon one particular shop—and ice cream parlor. Rose points imperviously toward the shops. "There."

He agrees. Rose leads him to the door, small hand encased in his much larger one. They stop at the glass counter, where the girl views the selection, and makes her order of a double scoop of strawberry, with fudge sauce and sprinkles. The Doctor orders himself banana swirl, with nuts, and pays at the register while Rose watches one of the shop boys scoop and prepare their ice cream. Her wonder and excitement is thrilling to see, really. After paying, he stands back to watch the shop boy hand Rose her cone with a hearty smile. She accepts, grinning too.

The boy offers forth the Doctor's cone, and he takes it before ushering his young charge out of the shop. They went to sit on the sculpted steel table sets outside on the sidewalk. Rose happily liked away at her dessert. The Doctor was slower about it, taking his time, and speaking between licks.

Sternly, he began a short lecture. "You can't tell your mum about this. Not at all. She'll thinks it's as bad as taking candy from a stranger, right?"

"Well, you are a stranger." The five-year-old points out.

"Right," He readily agrees. "But not really. One day we'll be great friends, I swear."

"How do I know?" Rose asks before taking a huge slurping lick.

"You don't. But trust me." He winks. "Now, what's the deal with your mum? Why are you so hesitant to go back home, eh?"

"Wot's 'hesistant?'"

"Uneager. Not exactly willing."

"Oh." She nods wisely.

"So, what is it, Rose? "

The girl drops her eyes. "Nuffin'."

"Rose," He prompts gently.

"She's always working!" Rose finally blurted out. "She's always out, and when she is home she never has time for me!"

"She has to work, Rose."

"I know, but…but even when she's got time off she's with her 'gals.'"

"So, you feel like she's abandoned you." He says, eyes serious. "But, you understand, without your father, she's under a lot of pressure. She has to care for you, go to work, take care of the house…can you really blame her for taking sometime to care for herself, to see her friends?"

"I—"

"She's sacrificed a lot for you. Can you understand?"

"…yes." Rose finally allowed. "I can."

"Good." The Doctor sat back in his seat. "Because she's working for you, Rose. Remember that. Are you done?"

She had just the cone left, which she was taking large bites out of, with loud crunching noises emitting from every bite. "Yeah." She replied around the sugar cone in her mouth.

"Alright then. Let's get you back home."

"But—"

"Your mum is probably sick with worry." He says firmly. She was done with her cone. All that was left in her sticky hands was a napkin, smooshed. "C'mon."

Rose reluctantly stands and follows him down the street, slipping her hand into his without question.

When they reach the estates nearly thirty minutes later, she is entirely "tuckered out." This weariness didn't stop her from chattering up a storm. Though, she had yet to ask what he would consider very important questions such as "What is your name?" and "Who are you?" Then again, perhaps these things weren't important in Rose's five-year-old mind. Just as walking in the middle of the road wasn't yet a no-no in her mind.

Before he releases her to walk up the sheltered stairs, he squats to her level, meeting her eyes fully. He takes both of her small hands into his. "Rose, listen to me. You've got to stop running away. Stay here, and stay safe."

"I am—"

"I found you in the middle of the street, Rosie. That's not safe you could've been hurt, or kill!" The Doctor lets out a breath. He is letting his emotions get away from him. "I just want you to be good." He breathes softly. "Just stay put, and stay safe. Can you do that?"

She nods.

"Can you promise me?"

She nods again, bobbing her head up and down quickly. He squeezes her hands before dropping them. But Rose picks them both up, along with his, just as he had held hers. A pair of serious little hazel eyes stare into his bright orbs. "Can you make me a promise?"

How can she be just five? He wonders. Surely this level of focus isn't normal.

"Of course."

"Come back."

He is both surprised and pleased. "Yes. I'll come back. I promise."

That was all she needed. Rose smiles and pulls away.

"Don't tell you mum." He reminds the girl as she leaves him to find the door to the stairway. Rose nods once again.

"I won't."

"And be good, Rosie."

"I will."

"Goodbye, Rose."

"Goodbye—" She turns to him, wanting to inquire after a name, realizing for the first time since the stranger had pulled her from the middle of the street that she did not know it.

He is already gone.

-XXX-

As he strides through the streets of London, hands feeling quite empty, he recalls the first thought he had upon seeing his young companion. Mortality doesn't occur to children until the age of seven. Children don't realize mortality until they're seven...

When would it occur to Rose Tyler?

Mortality-the realization of death. The moment you realize this beautiful, lovely thing called life eventually has it ends, like movies, storybooks, and even ice cream cones.