Why is my little sister so mean?

[MewWinx96]

She's falling victim to what 80% of young girls fall victim to every year... The Bitch's Disease. It's where girls turn into total bitches because they think they're all tough shit because they have close to everything they want. Symptoms include over use of Social Media (Youtube, Facebook, Twitter, Tumblr, ect.), sudden personality changes, whining and bitching when they don't get what they want, and doing whatever it takes to please peers. The disease is currently uncurable and only time will tell it's long-term effects. The disease has been present through out history, but had a much lower rate of prevalence. it was only recently with the popularization of Social Media that diagnosis rate has skyrocketed. I am not trying to bash your sister, I am just giving the facts of the disease.