http://en.wikipedia.org/wiki/Hensel_twins
Each of the twins manages one side of their conjoined body; They cannot feel any sensation on the other girl's side, yet they can somehow tell when to do something like scratch a mosquito bite on the other girl's arm. This, no one can really understand.[citation needed] Through it all, by coordinating their efforts, they are able to walk and run normally. They enjoy hobbies and sports including volleyball, basketball, kickball, swimming, cycling, and singing. They also play the piano and are avid computer users. Like many teenagers of their generation, they enjoy softball, digital photography, the internet, social networking, and talking on the telephone.
Despite sharing a body, the twins have different tastes in food and clothes. Some of their clothes are altered so that they have two separate necklines in order to emphasize their individuality. According to a TLC documentary (discussed later) in 2006, they negotiate what they will wear each day. They will usually have separate meals, but sometimes will share a single meal for the sake of convenience (e.g., each takes a bite of a hamburger).