‘NCIS’: How Mark Harmon’s Life Changed When His Sister Married a Pop Icon

by Suzanne Halliburton

Mark Harmon came from a famous family. NCIS fans probably know his dad won a Heisman Trophy and was a well-known sportscaster.

But did you know that he was related, by marriage, to some very famous folks. In fact, he said his sister’s family helped change his life.

Mark Harmon is the son of Tom Harmon and actress Elyse Knox. He also had two older sisters, Kristin and Kelly. Back in 1963, Kristin, who was then 18, married pop star Ricky Nelson. And Nelson was the son of Ozzie and Harriet Nelson, two iconic stars from the early days of television. The two starred in The Adventures of Ozzie and Harriet. The show ran from 1952-66. And Ricky Nelson was part of his parents’ show. Nelson then became a singer, with hits like Hello Mary Lou.

So you can see why Mark Harmon would love his sister’s side of the family. His parents also were friends with the famous couple, so the Harmons and Nelsons approved of the marriage.

In an interview with Parade magazine in 2019, Mark Harmon talked about what it was like to have such fame in the family. Harmon used to work as a lifeguard when he was growing up. And Ozzie Nelson would visit when Harmon was at the beach.

“We’d sit underneath my tower and we’d talk about big band music, as Ozzie started as a big band leader and Harriet was a vocalist.” Mark Harmon said.

Ozzie Nelson asked Harmon to fill in on his show, Ozzie’s Girls. An actor couldn’t be there. So Harmon came to the set and Ozzie Nelson showed him around the sound stage and editing bays.

“That changed my course,” Mark Harmon said. When Harmon graduated from UCLA, he got a job in advertising. He said he made enough money to buy a small house. And his job also came with an expense account. But he was hooked on acting, thanks, in part, to Ozzie Nelson.

Kristin and Ricky Nelson (Photo by Dennis Oulds/Central Press/Hulton Archive/Getty Images)

Mark Harmon Once Tried for Custody of Sister’s Son

His sister and Ricky Nelson had daughter Tracy right after they married. Tracy Nelson also became an actress. She was a star of Square Pegs, which also started the career of Sarah Jessica Parker. And she also starred in the Father Dowling Mysteries, which featured Tom Bosley from Happy Days. The couple had twins, Gunnar and Matthew, who formed the group, Nelsons.

But Kristin and Ricky Nelson had a tumultuous relationship by the end of their marriage in 1982. Mark Harmon helped his big sister get into rehab to treat her addiction issues.

She told People magazine “Nobody but my brother could have talked me into this because I trusted him. A voice inside me said, ‘For once in your life, let somebody help you.’ ”

Tragically, Ricky Nelson died in a plane crash in 1985. In 1985, Mark Harmon and his wife, Pam Dawber, filed for temporary custody of Ricky and Kristin Nelson’s youngest son, Sam. Mark Harmon already had been taking care of Sam, who was then 12, when he filed for custody.

Sadly, Kristin Nelson died in 2018. She was 72.

In the Parade interview, Mark Harmon talked of the love he had for his niece and three nephews. He called their relationship “a gift.”