Marlo Thomas, Phil Donahue explore 'secret sauce' of marriage with celeb couples in new book

Marlo Thomas and Phil Donahue won't be able to celebrate their 40th wedding anniversary on May 21 in in their typical fashion. The couple normally break away to spend time together in places like China, Indonesia, France and Italy but will instead stay put in Manhattan amid the coronavirus pandemic.

But they'll still mark the milestone with a new book about lasting couples, the first project the actress (and national outreach director of St. Jude Children's Research Hospital) and the groundbreaking talk show host have worked on together.

For "What Makes A Marriage Last" (out Tuesday, HarperOne, $29.99) Thomas and Donahue spoke with 40 couples to reveal "the secret sauce" that forms lasting unions.

In a phone interview, it's apparent that after four decades, they still really like each other. Thomas is quick to laugh at her husband's jokes, as when he says, "She didn’t get married until she was 104 years old."

"Forty-two," she corrects him with a chuckle.

Although Thomas says Donahue was reluctant to talk about their own union for the project, he relented after speaking to other couples, including Kelly Ripa and Mark Consuelos, Elton John and David Furnish, Melissa McCarthy and Ben Falcone, Al Roker and Deborah Roberts, Chip and Joanna Gaines and former President and first lady Jimmy and Rosalynn Carter, to name a few.

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In successful unions, "people don’t look for an escape route," Thomas says. "They’re not people who are afraid to face things that are difficult, and a lot of the people in our book face all kinds of challenges."

The conversations delve into obstacles that couples may face. Kevin Bacon and Kyra Sedgwick relay the stress of losing millions as victims of Ponzi scheme swindler Bernie Madoff. Jacqueline Jackson discusses the child her husband, the Rev. Jesse Jackson, bore in an extramarital affair. Ripa and Consuelos recount the time he was so filled with suspicion he boarded a plane from Boston to New York to check up on the morning show host, who told him she planned to spend the night cleaning the toilets.

"(Consuelos) went into the apartment and (Ripa) opened the door and was so excited to see him," says Thomas. "She had a johnny mop in her hand, and she was in an old bathrobe... She said he came (in) ran right past her, went all through the apartment. She said he was looking for somebody. He didn’t believe her, and it was earlier in their marriage. He said in the interview, 'I was very jealous in those days, but I’ve gotten better.'"

Thomas says the two couples laughed about it. Thomas and Donahue picked up several lessons in their chats.

"Kyra Sedgwick said something that I love," says Thomas. "She says, 'You go into a marriage you can’t go in with any Plan B. This is it… If you go in with your eye on the exit door – (thinking) if things get tough I can always get out here – then you probably will get out of there.'"

Viola Davis said, "'I thought marriage would be 50-50, but it’s not. It’s 100-100,' and It’s true,'" recalls Thomas. "You have to give all of yourself to it."

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Early in their marriage, Thomas and Donahue committed to traveling to see each other every weekend, while she worked in Los Angeles and he was in Chicago. The two became instantly infatuated when Thomas appeared on "The Phil Donahue Show" in 1977.

"We went out the very next night and were together from then on," Thomas remembers of their quick connection. "It’s so interesting – I mean, I went on a lot of talk shows in my life. I didn’t fall in love with Johnny Carson, you know?"

Donahue saw her as "a hangover guest," someone who, "even if you’re not very sharp, and you're not quick on the trigger, will somehow keep the balloon afloat, will keep the conversation going and save you, so to speak."

Thomas shares the couple's "code word," PHM, which stands for "a perfectly happy moment," which can happen when the two are admiring a sunset or really enjoying one of life's moments.

"I think to celebrate life and celebrate the good moments, there’s nothing corny about that, that is the very richest part of life," says Thomas. "And I think that marriage is a real cushion of life, humor is a cushion of life. Things that lift you up and hold you.

"I very much appreciate what Michael J. Fox said," she adds. "He said, 'There are days when I just can’t get up over a wall. I hit a wall and I can’t get up over it. I need somebody under me to get me over the wall, and every single time, it’s (wife, actress Tracy Pollan). She gets me over the wall every single time.'"

Says Donahue: "Now you see what I mean by a hangover guest."

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This article originally appeared on USA TODAY: Marlo Thomas, Phil Donahue's book explores marriage with celeb couples