Koenig is probably best known for playing Mike Seaver's best friend, Richard "Boner" Stabone on the sitcom Growing Pains. He was in 25 episodes of Growing Pains and also guest starred on episodes of 21 Jump Street, My Two Dads and My Sister Sam. Koenig starred in the 2003 fan film where he played The Joker. His father is Walter Koenig also an actor. Koenig disappeared on February 14, 2010. His parents said he showed signs of depression before he went missing. His body was found hanging from a tree in Vancouver's Stanley Park, on February 25, 2010.