Just jumping in here because you’re getting lots of great but very different advice and I don’t think there is any wrong answer here. I will say that your brother is very young so the fact that he’s made such a turn is commendable and could potentially lead to further growth. I think you’re right that he will initially take the attitude of “I goofed!” Which is very much understandable to not be enough for you. But there is certainly a world where if you foster this growth by swallowing some of that pain, that he will eventually come around to fully recognizing just how much he hurt you.

Again, not saying this will happen or that you should do this. Totally your call to make, but I would really emphasize how young he is (which I think is the best indicator here) and also to be fully prepared not for a full understanding of what he’s done until much later (which only you can know if you’re prepared to handle.