Keyboard issues

Can someone please help me figure out why my keyboard just completely died on me?
I was typing away like usual when my little sister started messing around with it—I have no clue what she actually pressed, but now absolutely nothing works. Not a single key will respond. :/

Does anyone know what might have caused this?

It could be a minor glitch. Check if one of your keys is stuck down. If everything looks fine, try unplugging the keyboard and plugging it back in...

Did you reboot? Maybe the system just froze up.

http://manualsbrain.com/en/manuals/222998/ this particular model

I suspect we might be looking at an issue with Sticky Keys.

Here. Do you have a workaround for this issue if you're running Windows 8 or 10?

If you're still running Windows 7, Here. Can you find some instructions on how to disable this?