Verified answer

how about ignore her. she most likely does what ever she does on purpose as she knows it bothers you. If she sees no reaction from you she will eventually get bored and stop. But if you react, which is what she wants, she will keep going.

Tell her to mind her own business. But she probably won't anyways. Sisters are always going to be nosy, like you can't really get around it. My advice....get better at covering up sh*t you don't want her to know. Good luck!

Use your smartphone and a password. Also try being nosy back at her (this reverse thing always works for me)