Well..! First I suggest to get a box with a lock on it to keep your valuable away! and tell her privacy is important to you and she needs to back off because one day she'll have kids and they wont appreciate her snooping around!
I understand why you had slapped her! there was nothing wrong with it, your mum wasn't thinking by telling you off, you shouldn't be punished for your sister being... an idiot really -.-
Your sister is probably stressed etc etc due to pregnancy, but that gives her no right to act like a child! :/
So, my best bet is to keep your stuff away from her and i guess you're just gonna have to put up with it for now :/ I really hope I helped you out! x
just hide the stuff you dont want her to see in another rm
lock ur stuff put a lock in ur room lock ur diary
Its a Cuban sandwich lol! And don't smack her! She is pregnant. Either ask your mom what to do or hide your stuff. smacking her will make her hate you lol. Or tell her again and if not just go through her stuff.