This photo provided by Office of George H. W. Bush shows a photo of former President George H.W. Bush that has tweeted on Friday, June 1, 2018 from his hospital bed while reading a book about himself and his late wife in Biddeford, Maine. Credit: Paul Morse | AP

KENNEBUNKPORT, Maine — When her granddaughter asked for marital advice, former first lady Barbara Bush told her, “You have to go 75 percent of the way.”

“Be thoughtful and make things nice for your husband or wife … it’s a two-way street,” she continued. “I believe I’ve had a very happy marriage and I’m having a happy marriage.”

It’s that 73-year marriage to former President George H.W. Bush, the longest marriage of any presidential couple in history, that is featured in a new book “George and Barbara Bush: A Great American Love Story.” It’s an intimate look into the private life of a very public couple written by their granddaughter Ellie LeBlond Sosa, and Kelly Anne Chase. In this first-ever family tribute, Sosa infuses fond memories of her grandparents and growing up in the Bush family with intimate interviews with the Bushes and their family friends.

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The book includes never before published stories, letters and photos from the Bushes long-time Kennebunkport summer home, Walker’s Point, and explores the enduring relationship of George and Barbara Bush from its beginnings at the outbreak of World War II, through his time in the Navy and his long career of service. Barbara Bush passed away in April of this year, just before the book’s release.

“I’ve witnessed my grandparents for the past 31 years of my life and knew they had something special, and I also knew that before me and my time there was so much more,” Sosa said. “I’ve heard stories over the years from family and from them and thought what a great story this would be to put all together, not only to share it with the world, but also as a keepsake for our family to have because we all look up to our grandparents so much and look up to their love story. To have everything together, the stories and the letters and photos, to have it all in once place, is a really special thing for our family.”

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Sosa and Chase, who first worked together when Chase — a magazine editor — worked on a story about the Bushes and Walker’s Point, reconnected for “George and Barbara Bush” in February 2017. Sosa said she first ran the idea of a book on her grandparents’ love story by her mother, Doro Bush Koch, who thought it was a good idea and suggested she speak to her grandmother, who Sosa calls “Ganny.”

“I talked to my grandmother in Maine and said, ’Ganny, we are wanting to write a book about you and Gampy and your love story,” Sosa said. “She’s like, ‘Well, I don’t know why you’d want to write about that. That sounds like such a bore.’ But she really was excited about it. We interviewed her three times throughout, so that was really special to have her included in the book.”

Sosa and Chase were given access to the Bush Presidential Library in College Station, Texas. Sosa said they poured through more than 100 scrapbooks “from every part of their life together” that included family photos, newspaper clippings, diary entries from decades ago, and the letters the couple wrote to each other. In one scrapbook, in an envelope at the bottom of the page, was a wishbone from the first Thanksgiving they hosted in 1945, Sosa said.

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“My grandmother saved everything over the years,” Sosa said, adding she told her grandmother about finding the wishbone and said she laughed and said, ”‘I remember that.’ I’m so grateful that she did. It’s like she knew many years down the road that people were going to look back and want to have all this.”

The process of compiling her grandparents’ story was like putting a puzzle together, Sosa said. “Take a letter from here, a photo from this part of their life, part of the diary entries from here, and kind of puzzle piece it all together into the story,” she said. “The book is somewhat of a chronological story of their life, but it’s through the eyes of their love story. It was a really fun process and very special for me.”

In the book, Sosa talks about the special relationship she’s had with each of her grandparents. She said that bloomed when she, her brother and mother moved to Washington, D.C. during her grandfather’s presidency, and they spent a lot of time at the White House.

“They both have this special way of making everyone feel so loved and special,” Sosa said, adding her grandfather was an “amazing letter writer” who used his words and writing, among other reasons, to share his love and support of his family.

In one letter to Sosa, when she was a junior in college in the fall of 2007 and going through a tough semester, Bush writes, “Your mom told me you tried to call me and she told me what it was about. My message back to you is that I love you, I am proud of you and I will always be in your corner. We all hit bumps in the road of life but you will get past this bump and go on to great things.”

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While Sosa said her grandmother had a reputation for being the “rule maker, when you really got down to it, she was just full of love and the only things that really mattered to her was her family and her friends,” she said.

Looking at her grandparents’ story, Sosa said it’s hard to imagine two people can have such experiences in one lifetime. “They went through some of the hardest things a couple can go through – losing a daughter, losing elections. They also had some of the greatest times together – raising their family, raising five healthy kids, they made it all the way to the White House,” Sosa said. “There’s a line in the middle of all that and that was their love. It’s just straight across all the time. That was the constant.”

Sosa said she believes much of their strength and unity as a couple comes from their shared love of family. “They surrounded themselves with family always,” Sosa said. “They made each other laugh every day. And, of course, they were fiercely loyal to one another.”

Today, Sosa lives in Boston and is happy to be so close to her family’s summer home in Kennebunkport. It’s where she met and, in 2014, married her husband.

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“Maine is such a special place, I think especially to me,” she said.

In her final interview with Barbara Bush, just 10 days before she passed away, Sosa asked if there was anything in life her grandmother regretted.

“I would have been nicer, thinner, smarter, more beautiful, more educated, I mean, all those things,” she said, as she made everyone in her hospital room laugh. “No, I wouldn’t have changed anything. You’re not going to talk to anyone happier.”

“I think she attributes that mostly to being George Bush’s wife,” Sosa said.

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