asked alan garcia not to talk about the shooting. >> you know, i would never mean to cut people off, but when i have done it, i feel like such a jerk, and i wave to them. i hope they can read lips when i say "i'm sorry." >> reporter: the case of road rage that began with yelling and ended with gunfire. >> so many what-ifs. >> reporter: racked with guilt, garcia says lyttlely asked to sit next to her big brother, isa isaac, just before the shooting. >> if i would have let her move her seat over six inches -- six inches. >> reporter: lilly loved the piano. loved life, and especially her brother. as parents, how do you guys move forward? >> because of that little guy over there. i have no choice but because of him. >> reporter: isaac still wears