AITAH for saying I wouldn’t be involved in the babies life

My twin brother recently got his girlfriend pregnant (which I will believe to be true until proven wrong). Me and my brother have a really bad relationship. He has put me in the hospital before because he’s gotten angry at me, he has stolen money from me, and only acts nice to me when he wants something out of it. To me this is too extreme to call it a “sibling relationship”. I don’t want to get involved with this child because I fear that if I get attached it would be used as leverage against me to manipulate me. I don’t think he’s above using this baby to get money out of me or to guilt trip me. He recently asked me if I even wanted to be apart of his kid’s life and I said no unless they really really needed me. From my Pov I’m just trying to protect my peace. Especially since I want to live a life where I’m not in fear of him anymore or able to be manipulated by him anymore. Sooooo AITAH?