Mark Harmon, best known for his long-running role on NCIS, has fans who have noticed how little he's aged over the years. Throwback photos show Mark looking virtually the same as he did in 1996, with his piercing blue eyes, defined brows, and floppy hairstyle remaining consistent. His two sons, Sean and Ty, also bear a striking resemblance to their father, with Sean even having played a younger version of Mark's character on NCIS. While Mark left the show after season 19, there have been hints that his character could make a comeback in future seasons. Mark and his wife, Pam Dawber, prefer to keep their personal lives private and do not use social media.