Bruce watched her and gave a half smile. "Have to stay focus Aurora." He put the batarang he had thrown back in his belt and watched her retrieve the batarang that had missed. "One momentary lapse in concentration and you can miss a target by centimeters to meters." He knew this was dangerous but he needed to prove his point. So as she walked back to him he suddenly, and without looking, hurled a batarang and struck the tree under a second, making sure the batarang sailed close enough to her ear so she'd hear it whistling.
"Focus is the key to succeeding in anything. Half focus means half concentration means that you could miss something."
It had been a lesson he had had to constantly instill in his side kicks. Because the focus thing applied not just to throwing batarangs and fighting crime, but also to life. Bruce had a gut feeling that Aurora was a smart kid. Maybe not as smart as her father, but smart enough to get away with things she wanted.