Jim and John Harbaugh aren't the only sibling rivals in sports! 

photo credit to twitter @ravens

- Vince (Pittsburgh Pirates), Dom (Boston Red Sox), and Joe Dimaggio (New York Yankees)

- Serena and Venus Williams (tennis pro's)

- Vitali and Wladimir Klitschko (heavyweaight boxing pro's)

- Eli (NY Giants) and Peyton (Indianapolis Colts) Manning

- Pau and Marc Gasol (NBA players... Marc was actually once traded for Pau!)

Check out the full list from Time Magazine here.