Face it - the kid is just genetically predisposed to express herself in this manner - she may even be hard-wired, and can no more control her reflexes than a snake can stop twitching when decapitated.
I know, I know, that is evil and uncalled for and an overly personal attack, but her venomous viper of a mother has encouraged all the right programming. Some creatures do not learn in the conventional sense of the word, they can only be trained. Grooming for the Supreme Court, perhaps? Certainly a high position in some future Democrat regime. Democrats are unable to form respectable governments, but they can create some very Machiavellian power combinations.
What's the deal with her boyfriend? Doesn't he realize there are tons of better looking chicks than Chelsea? Or is he willing to hold his physical revulsion in check for the sake of possibly marrying a celebrity? Believe me, if her boyfriend actually marries Chelsea, he will be cheating on her bigtime after the wedding.