Pretty much every betch has either diagnosed another girl or been diagnosed as suffering from "daddy issues." Women with daddy issues are prone to blowing guys in frat bathrooms, blacking out at sophomore spring fling, and purposefully fucking up in school. Think Serena Van Der Woodsen and Marissa Cooper. But nobody really talks about "mommy issues," which might actually be a lot worse. Like, you probably won't almost die in Tijuana, but instead have an eating disorder or OCD. It's a different kind of crazy.
Purdue University did a study of women and their mothers. They asked about the daughters' levels of depression, loneliness, sadness, and insomnia then asked which sibling was mom's favorite. The study found that "people who felt that they were the closest emotionally to their mothers were more likely to be depressed." They think favorites feel that way because they're obsessed with disappointing their moms or fucking up. So basically, giving a fuck makes you depressed.
The moral of the story betches: don't worry about being yelled at for the credit card bill or showing up drunk to family dinner. You probably won't be depressed about it later, but your suck-up younger sister will be in therapy for a while.