Laura Bush also shared what it was like for her to leave the White House after eight years there, describing a "feeling of buoyancy."
The hyper-vigilance that she and President Bush felt during their time in the White House slowly diminished, and she said she could "finally exhale."
"I didn't really expect that. I didn't really know what to expect when we left," she said. "I didn't really realize how stressed I was until I wasn't stressed anymore. It's a very stressful job."
The younger Barbara Bush told "GMA's" Roberts that she "loved" reading her mother's memoirs, finding out about her youth, her time in college and career as a teacher, and her parents' courtship.
Her father recently joined the digital age in a big way: This week, the former president launched his Facebook page. As of Thursday night, more than 100,000 people had "liked" it.
He's not the only member of the family to have embraced social networking. His wife also has her own Facebook page.
And that's not all.
"Mom tweets," Barbara Bush, 28, told Roberts.
"I've been tweeting on the book tour," the former first lady said. "I never thought I would do [it], but it's been really kind of fun."
She didn't know whether her husband also would start to tweet, but noted that it could happen as "the next step" in his book promotion.
"All of these things now go into publishing a book," she said.
The former president's memoirs, titled "Decision Points," is set to be released Nov. 9.
Click HERE to read a full transcript of the interview.