Batman's Second Worst Mistake (Abused Author X female Batfamily)

Alex Carabello was the third Robin, but he was suspected to be the secret love child of the Joker. So when he was taken in by Bruce Wayne, he was abused by Bruce, his cousin Kate and Babs. But, he wasn't so on a mission after Jaylene died, he was sent on a suicide mission, during that mission it was revealed to Batman, Batwoman 1, and Batgirl that he was exactly who he said he was, so Batman left and tried to save him but when he got there he saw Alex fighting the Joker so he threw a batarang towards the Joker, but it hit Alex and he fell to his death. Now he wants revenge, he was brought back and trained by the best of Batman's rouges, to exact revenge.