[Western Crossover] Searching for Vivian

The Nineteenth Test Subject has one question: who is the person who always calls her "Vivian" in her dreams? And who is "Vivian"? * Suppose Dick really did have a biological younger sister, but she disappeared during the circus accident when he was eight, and no one knew whether she was alive or dead. Many years later, during a mission as Nightwing, Dick encounters an enemy and accidentally spots a birthmark on their shoulder that is identical to his sister's. What would he do? Big Brother: Obviously, find her (and snatch her) back!!! * Saving this idea. Maybe it'll be in third person. It's about Big Brother looking for his younger sister. At first they're on opposing sides, so there'll definitely be plenty of fighting. His sister is a modified human with special abilities. She's been brainwashed, but somehow she still feels that Big Brother is familiar. Besides the family storyline, there'll also be a romance. Unless something changes, the pairing will be one of the two Robins, but I'm still deciding. Theme: Family, growth, and redemption.