Missy Cooper

Little is known about Sheldon's sister Missy Cooper, besides her obvious hotness and the fact they're fraternal twins.  This is due in part to the producers choice to so far have her in only one episode.  WTF?  At any rate, unlike Sheldon, Missy appears to be socially adept and seems to have the keen common sense of her mother.  I get the impression she has more in common with Penny than Sheldon.  

My favorite Missy Cooper quote, "Shelly doesn't like company. Even as a little boy, he'd send his imaginary friends home at the end of the day.'"

(Missy Cooper is played by Courtney Henggler)