Bowser Jr.

Bowser Jr. is a Mario character that participated in the Vancouver 2010 Winter Olympics, and The London 2012 Summer Olympics.

Mario & Sonic at the Olympic Winter Games
Bowser Jr.'s first Sonic appearance was Mario & Sonic at the Olympic Winter Games. He was a newcomer along with Donkey Kong, Metal Sonic, and Silver.

Mario & Sonic at the London 2012 Olympic Games
Bowser Jr. returned for the London Olympics in Mario & Sonic at the London 2012 Olympic Games.