The Secret Life Of ‘NCIS’ Star Mark Harmon’s Sister Kristin Harmon Nelson

Mark Harmon’s sister, Kristin Nelson, had quite the life before passing away in 2018 at 72 years old. Long before Harmon made a name for himself starring on NCIS, Kristin married into the same family that starred in the hit 1950s sitcom, The Adventures of Ozzie and Harriet. While Kristin seemed to have a bright future, her life fell apart at the seams amid a battle with drugs and alcohol. Here is a look at the secret life of Kristin and how Mark Harmon tried to help her along the way.

Mark Harmon, Kelly Harmon, Elyse Harmon, Kristin Harmon, and Tom Harmon
Mark Harmon, Kelly Harmon, Elyse Harmon, Kristin Harmon, and Tom Harmon | Photo by Ron Galella/Ron Galella Collection via Getty Images

Kristin’s early days

Kristin was born into a family that already enjoyed a small measure of fame. Her father, Tom Harmon, was a popular football player who won the Heisman trophy and was drafted into the NFL. Her mother, Elyse Knox Harmon, had minor success as an actress in Hollywood.

Things really turned around for Kristin the day she met Ricky Nelson, whose parents starred on the hit show, The Adventures of Ozzie and Harriet. According to People, Kristin adored the Nelsons as a young girl and later fell hard for Ricky.

Kristin and Ricky tied the knot in 1963 after she turned 18 years old. As soon as the marriage was official, Kristin appeared on The Adventures of Ozzie and Harriet as the couple’s new daughter-in-law. The part launched Kristin into the spotlight and forever changed her life. Kristin and Ricky welcomed their first child together six months after exchanging vows.

Their daughter, Tracy Nelson, would go on to become a child star and appeared with Lucille Ball in Yours, Mine, and Ours. Kristin and Ricky had three more children: twins Gunnar and Matthew, and Sam.

Ricky and Kristin’s marriage falls apart

Ricky and Kristin’s relationship started strong, but the couple soon faced obstacles as he continued his career as a rock star. In an interview in the late 1980s, Kristin revealed that things went south when she decided to go with Ricky on tour.

A life of partying, however, was not the solution and she quickly realized that they both had a drug problem. Kristin attempted to fix her addiction by going into rehab and briefly convinced Ricky to do the same.

Unfortunately, Ricky did not finish his treatment program and Kristin eventually filed for divorce in 1980. Over the next two years, the estranged couple fought a bitter custody battle in court before they reached an agreement in 1982. The next few years were hard times for Kristin, who made a living as an assistant casting director in Hollywood.

Unable to make ends meet, Kristin moved in with Harmon and his wife, Pam Dawber. Ricky, meanwhile, tragically died in a plane crash in 1985. Ricky was flying with other members of his band and his fiancée, Helen Blair. 

Mark Harmon steps in

With Kristin struggling with alcoholism, Harmon convinced her to go to rehab. Kristin finished a treatment program and later admitted that only Harmon could have convinced her to seek help. But Kristin’s relationship with the NCIS star quickly soured and the two fought over custody of her youngest child, Sam, in 1987.

Mark Harmon was granted temporary custody over the 12-year-old, and a judge ordered Kristin to stay 200 feet away from the Harmons at all times. Despite their obvious struggles, Kristin eventually won back custody after both sides reached an agreement.

Sam would go on to attend Boston College, where he started his own band called H Is Orange. He opened up about his mother’s life in an interview in 2016 and revealed that she had retired to a home in New Mexico. Sam also shared how he and Kristin remained close over the years and worked out their differences.

Kristin passed away from a heart attack at the age of 72. Her oldest child, Tracy, confirmed the sad news on social media, calling her death both unexpected and sudden.

Mark Harmon has not commented on his relationship with Kristin over the years, so it is difficult to say if they were close when she died.