Britney Spears gave an unexpected visit to a group of sick children at Miami Children's Hospital on Saturday (March 7). Just hours before hitting the stage as part of her world tour, the ‘Womanizer’ star enjoyed some time with the youngest patients of the facility while posing for photos. Besides, Britney has donated $100,000 to the Big Apple Circus Clown Care program, which brings clowns to entertain young hospital patients.