Hit your sister day
Grab your sister, smack her in the face and if anyone gets mad at you for it say its smack your sister day
Friend: *smacks their sister*
Friend 2: Dude!! Why did you do that?!?
Friend:Dont worry, its Hit your sister day
Friend 2: Dude!! Why did you do that?!?
Friend:Dont worry, its Hit your sister day