Sofonisba Anguissola was the first Italian woman to gain worldwide reputation as an artist. Her painting, A Game of Chess, is not a religious image or even an image of any real importance; instead, it's a picture of an everyday recreational activity.
Each character has a different expression on her face, making them all unique personalities; each is in movement, making them dynamic beings; each is a different age; the list goes on. In short, it is very realistic. In art, especially in portraiture, it is almost a rule that as importance decreases (such as rank), formality is relaxed and realism is increased. The event occurring here (a game of chess) is of lesser importance; therefore we see the heightened realism.