The Williams sisters have been close since growing up together on the tough streets of southern California. But when Venus and Serena face each other on the tennis court, they each play to win. With their amazing talent and star power both on and off the court, the Williams sisters are among the biggest celebrities in the sports world. They're also two of the best tennis players to ever set foot on a court. Learn more about Venus and Serena's incredible journey to the top of the tennis world.