How many younger brothers does Mario have?

Mario has one younger brother, Luigi. Both are characters in Nintendo's "Super Mario" series of video games. Luigi first appeared in the 1983 arcade game "Mario Bros.," set in the sewer system of New York City.

The games follow the adventures of Mario in the Mushroom Kingdom. He is often joined by Luigi and sometimes by other fictional characters. Players control Mario as he runs and jumps on top of platforms and over obstacles in various levels with different themes. "Super Mario" is the best-selling video game series ever, with more than 262 million copies sold. The game series is part of a larger "Mario" franchise that includes TV programs, movies and merchandise.