Sorry but how is slapping someone a nice way of explaining that something is wrong? So, if your brother had calmly explained to you that he didn’t think it was appropriate for you to swear and he didn’t want to hear it again you wouldn’t have listened to him? If he has enough authority to slap you I’m sure he has enough authority to give you a serious talk. These things need to be explained in a reasonable, calm way…violent actions get you nowhere imo.