Should I pay my narcissist brother back?

I stole from him because my life is not going well, and I am currently struggling so hard to pay my medical/pet bills. I regret it, and it's my first time ever stealing from someone. He stole big money from my parents in the past, borrowed money from random people but never paid anyone back, and he got away with it coz "he's family, and their son". Now he's angry that it happened to him and claims I stole an amount bigger than what I actually stole, which I have proof that he's wrong. For anyone who don't know, everyone in my family are narcissists, and I live with them, and I'm currently being condemned, and forced to pay that amount. I'm the family scapegoat, and it's so unfair that were both treated so differently. Should I or shouldn't?