“I’m a fairly private person,” Selleck shared with People in 2020. “And I’ve always treasured the balance between work and time with my family. It’s always about them.” This sentiment has guided Selleck throughout his career, ensuring that his focus remains on Mack and their children.

Mack, who spent her mid-20s starring as Rumpleteazer in Cats, played a pivotal role in Selleck’s life. The musical not only marked a significant achievement in her career but also brought her and Selleck together. In 1983, while filming Lassiter in London, Selleck frequently attended Cats performances — a habit that puzzled his co-star Jane Seymour. “He kept telling me how great Cats was,” Seymour told PEOPLE in 1984. “I thought it was good, but I couldn’t see going back a dozen times.”

After a dinner date arranged by Mack’s agent, their relationship blossomed, and Mack eventually moved to the U.S. to be with Selleck. On August 7, 1987, the couple married in a secret ceremony at a Victorian-style chapel near Lake Tahoe, Nevada. The wedding was so private that even the minister was unaware of their true identities, expecting to marry a “Tom Jenkins” and a “Suzie Mark.”

The couple welcomed their daughter, Hannah Margaret Selleck, on December 16, 1988. Raising Hannah on their family ranch, Mack and Selleck believed it provided the best environment for her to grow up. “We both thought it was the best environment for her to grow up,” Mack told People in 2012.

Selleck added that their rural lifestyle positively influenced Hannah’s maturity. Hannah, now a decorated equestrian, began riding competitively at age 10 and later founded Descanso Farm, which focuses on developing top-quality horses for show careers.

Selleck also has a son, Kevin, from his previous marriage to actress Jacqueline Ray, which ended in 1982. Following Hannah’s birth, Selleck and Mack retreated from the spotlight to focus on their family, settling on a 65-acre ranch in Ventura, California. The ranch, once a working avocado farm, became a sanctuary for the family. “My relationships and my ranch keep me sane,” Selleck told People in 2020. “I do grunt work and I make the rounds. I like watching things grow. It’s a retreat.”

Mack, who appeared in a few episodes of Magnum, P.I., as well as Frasier and ER, has supported Selleck’s decision to maintain a balance between work and family life. Selleck’s decision to leave Magnum, P.I. was one he never regretted. “It took a long time to get off the train,” he reflected. “My first priority is time with my family,” he said, emphasizing the importance of nurturing his marriage with Mack.

In an interview with People in April 2024, Selleck shared what he treasures most about Mack: her “friendship” and “sense of humor.”