Yes.
But this girl is not exactly a "kid" but rather.. a teenager since she is 15 years old.
She is my best friend's younger sister (whom used to be my best friend as well) pretty much became really delusional and messed up in her head after she lost her account due to "hacking" or something.
For some reasons, the girl thought I hacked her and took all the virtual items and money from her, even though she never gave me any of her account information, but she did give them out to basically every online boyfriend she met on first few days or so. I did not hack her, and I even proved to her on Skype by screen-sharing. But she just continue to be a moron anyway.
So yeah, she decided to stop being my best friend and won't even hear me out. She basically started to throw death threats at me, and saying that "no one like me because I'm a f**king fat deaf pig that deserve to be slaughtered and roasted on a fire". And that she keep telling me to go to hell.
It's funny because she's one of those people that is a very strong Catholic, but as far as I can tell, she won't be appreciated by the "god" if she continue to do so (which is funny because I'm an Atheist, and even I can tell that).
Apparently it started to affect the way she behaves in real life as well, and she threw a knife at my best friend once (luckily my best friend caught it with her own hands), and she would throw a tantrum everyday and their parents doesn't even know what to do. The girl soon started to demand things such as few hundred bucks weekly, or getting to keep my best friend's stuffs such as coat (basically forcing my best friend to give it to the girl). If the girl doesn't get what she want on each day, she would start to throw a tantrum, and sometime even threatens to "run away" which basically made the parents give her stuffs.
My best friend even got to a point several times where their parents couldn't pay the bills to keep the power so the power went out, and they barely had any money for food because they keep throwing the money at the girl to keep her calm. My best friend tried to confront to her parents, but most of the times, the girl would overheard them, and suddenly barge in, throwing a fit saying how it's not true. If my best friend continued to try and tell their parents. The girl would end up hitting her own older sister, and their parents can't really do anything about it.
I remember one time, when me and my best friend webcammed on Skype, her younger sister caught my best friend webcamming with me, and she threw a fit because basically... it's me.. she still have held a grudge against me, so she started to give a middle finger to my best friend, and tell her that "you're a f**cking idiot, but oh well, you can still be friend with him as long as you know he hacked me."
After a bit, their mom is starting to be blinded by the girl (as in, mom pretty much takes her side over everything now over my best friend (who is mom's older daughter). She pretty much throw tantrums over everything, and forces her mom to get it for her. Even the girl would wake up her mom at 2 am in the morning just to take her around for shopping, or just to drive around. She also would force her family to go to grandma's house which is around few hours away, her whole family (parents, and her older sister) and while at there for basically literally a hour, she want to go back home. If the parents told her no, she would start to hysterically cry so parents had no choice but to take the two girls back home.
Well.. that pretty much summed it up. I do know the girl have a "thyroid condition" which affect her hormones which can effect what she thinks. But from my opinion... no matter what condition a person have, the behavior is not acceptable, and parents should've done something about it instead of just babying her. Sad thing about this is... it first happened last summer (around July, with the hacking incident like I said in first part of post) where the girl is more than 14 and a half.