Sometimes the Internet saves people from being sex trafficked. Good! But sometimes the Internet beats up on an 11-year-old girl, posting her address, phone number and making her cry. Bad. This is what happened to Jessi Slaughter.

Here is the video you may have seen of 11 year-old Jessi Slaughter (not her real name) and her dad freaking out.

It's funny! But we're left wondering, what happened? Here's how the Internet's rage—funneled by Tumblr and 4Chan.org—ended in this sad and ridiculous scene.

Before Jessi's Internet fame was secured with this video, she was already an unfortunate microcelebrity among Internet tween scenesters. Earlier this month, Stickydrama—a crowd-sourced gossip website for 13-year-olds who loiter in mall food courts—dubiously linked her to the lead singer of emo band Blood on the Dance Floor, Dahvie Vanity. When a Stickydrama user asked Jessi for comment, she said: "gtfo dahvie and I dont exist, I'm just a fan." The user concluded: "If Dahvie were a pedophile, why would he pick her! Other than the fact she's a slut!"

So, Jessi had haters. A few days ago, she posted this YouTube video calling them out, issuing such threats as "If you can't stop hating, you know what? I'll pop a glock in your mouth and make a brain slushy." Ha ha. Unfortunately for everyone involved, someone posted it to the Internet's scariest hive mind: 4Chan.org's notorious /b/ message board, and Tumblr.

The Internet started picking on Jessi Slaughter relentlessly. But it was more than just mocking: People started circulating Jessi's real name, phone number, address and links to all her social networking accounts. Someone prank called her. According to Encyclopedia Dramatica, pranksters spammed her Facebook and MySpace accounts, had pizzas delivered to her house and were considering sending call girls off Craigslist to the address. (Encyclopedia Dramatica currently has a three part section on "How to troll" Jessi: 1) "There are pics of her holding her boobs" 2) "Tell her to kill herself" 3) "Tell her dad that we are going to beat her up.") Slaughter's information and videos also shot through tumblr, aided by the blogging platform's reblogging system.

Eventually, Jessi's dad filmed himself yelling at the camera. Boing Boing picked up the video and a meme was born. Actually, the video's so good it spawned at least three different memes: "You dun Goofed," "Consequences will never be the same" and "Cyberpolice."

Here are some important lessons from this tale:

1. What are your kids doing on the Internet? Normally, we find fears about kids on the Internet the product of technophobic hysteria. But this case is a very good argument for why parents should at least be vaguely aware of what their kids are up to on the Internet. Is your 11 year-old girl embroiled in an underage sex scandal with the lead singer of a popular emo band? Is she threatening to shoot people on YouTube videos? Maybe now is the time to invest in good parental control software before she becomes a meme.

2. Tumblr is becoming a home for trolls. Tumblr was originally the good-natured domain of hip New York creatives. It was, on balance, a creative force on the Internet. But the role it played in trolling Jessi Slaughter shows that Tumblr is developing a nasty side as well. Tumblr founder David Karp better get on this before Tumblr becomes 4chan with a slick minimalist interface.

3. Don't pick on 11 year-old girls. Seriously. No matter how dumb they seem—no matter how much they might seem to deserve it—they are, at the end of the day, 11 year-old girls. You wouldn't make an 11 year-old girl cry in real life; why do it on the Internet?

Update:Jessi Slaughter placed under police protection after death threats