What was the name of Jackie Robinson's older brother who won an Olympic medal?

Jackie Robinson's older brother who won an Olympic medal was Mack Robinson.

Mack was the nickname of Matthew MacKenzie Robinson, one of Jackie's older brothers. The Robinson family moved from Cairo, Georgia, to Pasadena, California, after their father left, and Mack helped inspire Jackie and his siblings to pursue athletics despite financial hardship and racial barriers.

At the 1936 Summer Olympics in Berlin, Mack Robinson won the silver medal in the 200 meters. He finished behind Jesse Owens, who won four gold medals at those Games. Mack also set a junior-college broad-jump record that Jackie later broke while attending Pasadena Junior College.

The brothers remained closely connected to Pasadena. Mack graduated from the University of Oregon and later became active in Pasadena civic life. The Pasadena Robinson Memorial, dedicated in 1997, honors both brothers with large bronze busts. A common mix-up is treating Mack as Jackie's middle name or assuming he won gold; his Olympic medal was silver, while his full name was Matthew MacKenzie Robinson.