Having a Writer's Block.
This is all I have so far:

She didn't look like my sister, lying so lifeless in the coffin. My little sister always had rosy cheeks, I remembered her that way. It was weird. It didn't feel like she was really dead. And that was not her in the coffin. I mean, it was of course, but when I looked down at that empty body it didn't seem like my sister was really dead. They made her look really good considering she'd been stabbed in the chest five times and once in the throat. My mother stood next to me sobbing, but I couldn't seem to find any tears. Sure, I was sad. Devastated, actually. But I was still in shock of it all.

I was the only one who knew who her killer was.

The cops couldn't find him anywhere. Should I take things into my own hands? Probably not. I'd probably end up dead. The last thing my mom needs is two dead daughters.