Your big sister, Karen is a genius with 300 IQ and 7 PhD's, so she's smug as hell, lol. She's got a personal research facility under the house and sells all sorts of things to the government. Your parents let her do whatever she wants because she's the "favoured child" and you're her favorite test subject. She's a pervert who experiments on you in your sleep, but deep down, she loves you to bits and is down bad for you.