Chapter One: Upended

"So, if we put this to use here, then-"

"I'm sorry to interrupt, Mr. Stark, but there's a young woman here to see you."

Tony frowned. "Who is she, Jarvis?"

"I'm not sure, sir. She says her name is Christina and that she won't leave without speaking to you."

Tony raised his eyebrows and glanced at Bruce, who nodded. "Alright, send her up. Thanks, Jarvis." He nodded to Bruce. "Be right back."

"I'll keep working on this," he replied, without looking up from the program.

Tony started walking downstairs, when he was stopped by Pepper. "There's a girl outside..."

"Yep. I'm going to see what she wants."

Pepper nodded. "Good."

The elevator opened, and the young woman stepped out. She had thick-rimmed glasses; long, straight, dark brown hair and brown eyes, highlighted by thick rings of black eyeliner; her lips were tinted red and set in a thin line. She was wearing blue jeans, a black tank top, and a black sweat jacket.

"Tony Stark?" she held out her hand.

"Yes," he replied, shaking her hand. "And you're Christina...?"

"Call me Chrissi." she replied.

"Ah." He nodded and motioned for her to sit. "Can I get you anything to drink, Miss...?"

"No, thank you. And it's Stark."

Tony raised his eyebrows. "Your last name is Stark?"

She nodded. "That's why I'm here. I...I'm your sister."

"My sister."

"Yes. Well, half-sister."

Tony studied her. "What is it you want? I'm not giving you any money. You'll have to come back tomorrow with a better scheme." he said sarcastically.

Christina frowned. "I know it's unbelievable, but I'm not lying."

"Do you honestly expect me to believe-"

"No. I don't. I already figured you'd take some convincing." She reached into her purse and pulled out a folder. Handing it to Tony, she said, "That's my birth certificate, my driver's license, child support checks from your father, and a paternity test, further proving that we have the same father."

Tony studied her license. "You're only nineteen. How did you get to New York from..." he searched the paper, "LA?"

"I drove."

"You drove?"

"I don't have the money to fly."

Tony looked at the paternity test. "...how long have you known...?"

"That I had a brother or that my brother is you?"

"...Both."

"As long as I can remember, and a few months. In that order."

Tony looked at her skeptically. "How do I know you're telling the truth?"

Christina leaned forward. "When I was six, a man came to my house to talk to my mother. He brought pictures of a little boy and a circuit board, a little boy and an engine." She pulled them out. "That's you, isn't it?"

Tony said nothing.

"He made it clear that you were his favorite, the special one, the golden child. My mother would write him letters, sent him pictures of my publications, my report cards. Nothing was good enough. He told me I'd never be as smart as you. This-" she jabbed one of the photos with her red fingernail-"was what I had to do to get his approval. And even then it wasn't enough. I'd never even met you and I was living in your shadow."

Ignoring that, Tony asked, "Where is your mother now?"

A spasm of pain crossed her face. "She's dead. She died a few months ago."

"I'm sorry," said Tony. "Is that why wanted to find out who your brother is?"

She nodded. "She told me it was okay, if I wanted to look for you now. In the past, if I ever mentioned you or your father, she would get angry, yell at me to forget it. But I couldn't. When you're five and all the other kids have a dad and you don't, you can't forget it."

"How did you find me?"

"Google. It was easy. I never even knew your name, and I went to boarding school most of my life, so I barely knew anything about Stark Towers or Iron Man. People gave me weird looks, asked questions, but I didn't think...I thought she would've told me. My mom said it was just a coincidence, and that's what I believed. Then when she died, I searched the name she gave me. Tony Stark. And there you were."

Tony smirked. "And am I everything you ever wanted in a big brother?" he said sarcastically.

Christina regarded him seriously. "Well, you're certainty not stupid. Or gullible. So I supposed that's a start."

Tony said nothing, and studied her papers again.

"Don't you have some fabulous machine that can prove that those papers aren't fake?" she asked.

"Of course I can. Jarvis?"

"Yes sir?" Jarvis answered. Christina jumped. Taking no notice, Tony said, "Tell the big guy I'll be back in a moment."

"Of course sir." replied Jarvis.

"...another one of your toys?" asked Christina.

"Actually, yes."

She smirked. "And given your message to the 'big guy'-Dr. Banner?-I'm assuming this visit is over."

Tony raised his eyebrows. "How do you know it's-"

"Oh, I found plenty of stories online about the Avengers. I saw it on the news, too. I saw everything that happened here, but I've got questions and you've got the answers I want. Another reason to come and find you."

Tony stared at her, then held up the folder. "May I hold onto these for a bit?"

"Of course."

Tony studied her. "Where are you staying now?"

"At a friend's. Fifth and Lexington."

"Can you come back tomorrow morning?"

Christina smiled and stood up. "I'll be here at nine."

Once more, she held out her hand. Tony shook it, then led her to the elevator.

"Thank you for your time." she said, just before the doors closed.

Tony walked back to the room where Dr. Banner were working on the Iron Man suit. Bruce looked at him questioningly.

"You look like your world's just been upended. Who was that?"

Tony glanced at him, then said, "My sister."

Bruce frowned. "You have a sister?"

"Apparently." He handed him the folder. "I told her to come back in the morning." He nodded towards the folder. "What do you think?"

"...Tony, I think these are legitimate."

Tony sighed. "I was afraid you'd say that."

Bruce shrugged.

"So, what now?" Tony asked.

Bruce shrugged again. "It's up to you, ultimately. But you should at least give her a chance. Where's her mother?"

"Dead."

"Then you really should take her in." Tony stared at him. "Look, she just lost her mom, she's never had a father figure, then she finds out she's got a famous older brother. Her life has been upended too. She's just looking for her family."

"I suppose."

Bruce glanced at his watch. "I've got to get back to S.H.E.I.L.D. You better start explaining this to Pepper."

Tony sighed.

Pepper, too, suggested taking Christina in. "Tony," she said, touching his arm, "I know it's a lot for you to take in...but I know you'll be a great older brother."