David McCallum and his wife Katherine Carpenter have been married for more than 50 years and share two children, Sophie and Peter. And while her husband is a star of a wildly popular TV show, Carpenter has quite the impressive background as well (per the Daily Express). She is a former actor and model who has made appearances on "NCIS" throughout the years. The couple first met in 1965 during a photo shoot in New York to promote "The Man from U.N.C.L.E.," which McCallum was starring in at the time and Carpenter was modeling for. Along with making cameos on "NCIS" with her husband, Carpenter also works with McCallum on various philanthropic ventures. 

The two aren't the only ones who work together on set, though. Mark Harmon, who plays lead man Leroy Jethro Gibbs, has brought both his son, Sean Harmon — who played a younger version of Gibbs — and his wife Pam Dawber into the fold. Dawber is set to play a recurring role on the show (via TV Insider). The familial nature of "NCIS" is just one of many reasons fans can't get enough of it, and it must be a great place to work if so many family members are heading to set.