Repression

You panic! You don't know what came over you. It was just her constant nagging, her verbal abuse, it just got to the point where you couldn't take it anymore. You don't want to kill anyone else.

As you attempt to go out your window, but your sister is already up the stairs and sees what you've done. She also calls out to you.

"Stop! You don't need to run away! Its okay. Just come back inside."