Mark Harmon is known and loved for his portrayal of Agent Leroy Gibbs in the long-running drama, NCIS.
The actor has enjoyed an illustrious career, appearing in various major films and TV shows over the years. But did you know he's not the only famous face in his family?
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While fans of the star may know that he comes from a very well-known family, they may not realize that he is related to actress Tracy Nelson, who is Mark's sister, Kristin Nelson's daughter.
Tracy, whose father is famous musician Ricky Nelson, is an actress who has appeared in various popular television shows. She began acting at a young age, appearing in the 1968 comedy film Yours, Mine and Ours at just five years old.
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Tracy landed guest roles in several major TV series over her career, including Seinfeld, St. Elsewhere, and Will and Grace. The actress also co-starred in the mystery series, The Father Dowling Mysteries, playing Sister Stephanie for its three seasons. Tracy was also a series regular on Aaron Spelling's Glitter, A League of Their Own, and the Australian television series The Man From Snowy River.
Mark's niece, Tracy Nelson, is an actress
Tracy comes from a long line of entertainers. Her great-grandparents were vaudeville performers Hazel Dell (née McNutt) and Roy Hilliard Snyder, while her paternal grandmother Harriet Nelson, was the star of the ABC sitcom The Adventures of Ozzie and Harriet, which ran from 1952 to 1966.
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As for her parents, her father Ricky Nelson was a hugely popular musician and actor. He began his career as a recording artist at the tender age of 17 and went on to place 54 songs on the Billboard Hot 100 between 1957 and 1973. The expression 'teen idol' was even coined to describe Ricky and his fame.
