Tony Shalhoub thinks "mutual respect" is the key to a happy marriage.

The 70-year-old actor has been married to 'Days of Heaven' star Brooke Adams, 74, since 1992 and has JOsie, 35, and Sophie, 31, with her ad admitted that he and his wife have been together so long because they have both been willing to "forgive" over the years.

He told Closer US: "Mutual respect and patience, I always feel like a successful marriage is one that has an equal number of apologies on both sides. People have to be willing to be humble, be forgiving, and be apologetic and not hold on to slights. I'm so fortunate, she's the right life partner for me."

The Emmy Award-winning star is known for his roles as Antonio Scarpacci on the 1990s sitcom 'Wings' and more recently has starred in Amazon Prime hit 'The Mavelous Mrs Maisel' but explainedaway from work that his time is taken up with his family as he relished in his role as a grandparent.

He said: "I have two daughters and two grandchildren. As I said, I also have nine siblings, so family keeps me pretty busy. I also like to read. I try to keep a good balance between my work and my personal life.

"[Being a grandparent] is fantastic. You get to spoil them and then hand them back when it gets to be exhausting. But they're the light of our lives."

The 'Monk' star began his career on the stage more than 40 years ago and Tony for his role in in the Broadway musical 'The Band's Visit' in 2017 and admitted that he would love to tread the boards again whenever possible.

He said: "I love all of it. I always base my decisions on the material rather than the medium. Theatre is great. It's fun. It's how I started in this business, and I plan to keep returing to the theatre whenever possible.

"But I think when you have good material and you're working with people you admire and respect, that's all that matters."