I feel like I would be the one threatening my sister with a knife, but never actually do it. Then the girl would tackle me to the ground, rip the knife from my hand and either threaten to stab me or put it back in the knife drawer, then go pet our cat. While Momo would purr, I'd try lock the door to my room before realizing something. 

"Wait. I don't have a lock on my door, I'm gonna die!"
While I scream about dying, my sister will probably be chilling on the couch watching Project Runway. Lol. I would never use violence against someone I can't win against, now my other sister... Maybe. But not with a knife, that's awful.

Simple and effective. Why did I read you just now?

Wow, this was interesting! It made me feel very unnerved at the point where he grabbed the knife. Because it was so tense, I was expecting a shocking ending, but all the tension was relieved at the last minute, haha. I might have liked a darker way of ending it (wow what's wrong with me, I used to love happy endings but now I'm becoming twisted! XD) but your writing is fantastic and I will read more of your stories! ;)

I wonder if it was tails or not.

Funny and dramatic. That was really a nice story