Kelly has always shown up on time and prepared. Between that and her dead pan/quiet expression off camera, it's easy to assume she's on drugs. Really, the girl is just money motivated. I've never seen anyone love money so much (well, maybe other than me). She doesn't have a lot of interests and isn't into partying or going out except to restaurants. She just loves having money and being left alone to read or hang out at home.
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"What I do know is that if Karen Carpenter and Mama Cass Elliot had shared that sandwich they'd both be alive today." -Michael K