A/N: Written for the "Look Who's In Town Now" theme at Batfic_Contest on Livejournal.
A Thousand Reasons
Barbara had a thousand reasons.
She wanted to be strong, she told herself.
After being held hostage by Harvey Dent along with her mother and older brother, Barbara knew the importance of being able to defend yourself.
She wanted to help Gotham, she told herself.
After 17 years of watching her father defend Gotham's people, she knew the value of being a hero. She knew that she could fight.
Batman couldn't do it alone, she told herself.
Gotham was too big, its enemies too strong. New threats arose every day, and old threats seemed to slink back out of the shadows.
"I know why you're doing this," Batman told her, "and I don't approve."
Barbara had just finished putting the custom-fitted mask over her head, the one that Bruce Wayne had ordered 10,000 of just for her, completing the look. She already bore the armor designed by Lucius Fox, the memory-cloth cape secured on her back.
"You don't approve?" Barbara said. "But you did approve—like literally, I think you actually had to approve the funds for all this fancy gear."
"I watched you grow up. I know Jim Gordon, and I know you well enough to know you'd just go out and do this on your own without my help."
"You've been training me for months. You think I'm not ready?"
"You're ready. You're fully capable of handling yourself in a fight."
"So what don't you approve of?"
"You think you need to earn your father's love. You think that James is his favorite."
Barbara froze. She'd never let herself face this reality before, but as soon as Batman spoke the words, she knew that it was true. Barbara had a thousand reasons for doing this, she'd thought. But now she knew there was really only one.
"You were there," she countered. "You saw what happened when Dent pointed the gun at James."
"I don't approve of your reasons," Batman said. "But I do approve of you. I trust you, and I can use your help."
Batman clicked open the doors of the Tumbler and got into the driver's seat.
"You have nothing to prove… Batgirl."
Batgirl smiled, and got into the seat next to him; and together they drove off, out of the Batcave, and into Gotham City.