‘NCIS’: Why Mark Harmon’s Son, Sean Harmon, Made an Appearance on the Series

by Madison Miller

Mark Harmon has been the leader of the mothership “NCIS” since 2003. He has been like a father figure of authority in the long-time series.

Harmon even renewed his contract for another year in order to keep “NCIS” from getting canceled.

While he is a Papa Bear to “NCIS” fans, Harmon is also the father to two sons. He has been married to actress Pam Dawber since 1987. The couple had Sean in 1988 and Ty in 1992. The two boys have kept a rather low profile, however, Sean Harmon has stepped in to play a younger version of his father in the past.

Sean Harmon as Mark Harmon on ‘NCIS’

According to IMDb, Sean Harmon has been the flashback, younger version of his father on several episodes of “NCIS.” He was on the episodes called “Life Before His Eyes,” “Engaged: Part I,” “Engaged: Part II,” “Mother’s Day,” “Deliverance,” and “Heartland.”

In addition to playing a younger version of his father, Sean has had minor roles in other shows as well. He was in “NCIS: Los Angeles” in 2015. He played Sgt. Terry Scott in “Ten Thousand Miles.” Sean was also in “Alina” in 2019.

His IMDb page also says that he is in post-production for the Joshua Mabie movie, “Thicker.” Sean Harmon is also a stunt double and has appeared in “Dumb and Dumber To” and “American Reunion,” amongst others.

There was no one better to play a younger Leroy Jethro Gibbs than another Harmon.

Other Family Members of Mark Harmon

In addition to his two kids and wife, Harmon has a few other noteworthy family members.

His godfather is Forest Evashevski. He was an influential college football coach that was inducted into the College Football Hall of Fame in 2000. Evashevski was the coach at Hamilton College, Washington State College, and the University of Iowa. He served most of his career in Iowa.

The “NCIS” star’s father was Tom Harmon. He also had a legendary football-related professional career. He was a halfback for the University of Michigan Wolverines. Tom Harmon won the 1940 Heisman Trophy, which is given to the best college player in the nation, for his success in the sport. He played two seasons for the Los Angeles Rams and later worked as a sports broadcaster.

Mark Harmon played college football as well for UCLA.

His sister is Kelly Harmon. She is an actress and model most known for doing Tic Tac commercials. Kelly also was on “Bay City Blues” in a regular role. She made guest appearances on shows like “Battlestar Galactica” and “CHiPS.” His other sister is Kristin Harmon. She is a painter, actress, and author. Kristin also was once married to musician Ricky Nelson.