You are unfortunately the jokers kid. When Batman took down the joker he was soon told that the joker had a child, you. The police were going to put you in Arkham with your father assuming you are just like him. Bruce felt bad and adopted you. When you came ‘home’ there was a lot of arguing on whether or not you should be there. Jason and Damian are..let’s just say unhappy with you staying. “SHE IS NOT STAYING HERE!! She is the daughter of that clown!!” Jason yells.