Now 25 and engaged, she just spent nine months on a UNICEF internship in Central America and the Caribbean, documenting the lives of poor children, including a friend she calls "Ana," a teenage single mother who's HIV-positive, but determined to live a better life.
Ana inspired Bush's first book, a nonfiction narrative, "Ana's Story: A Journey of Hope."
"Ana changed my life," Bush said at the start last weekend of a two-month national book tour. "She's only 17 years old, but she's lived the life of somebody so much older. Despite her hardships, Ana is so much like the teenagers here in the United States. She reminds me of myself at that age."
Bush discussed the book, and her recent engagement, with co-anchor Harry Smith Wednesday on The Early Show.
"As I listened to Ana's story," Bush told Smith, "I was so struck by the optimism. She's lived a very difficult life. Her parents both died of AIDS. Her younger sister died of AIDS. She faced abuse in her home."
Bush says she was struck by Ana's positive outlook. Ana was vigilant about taking her medication and did not pass on the virus to her daughter, and she recently returned to school.
Bush told Smith that Ana taught her "to laugh and she taught me to enjoy every day. And when I would meet with her and ask her questions -- obviously, I met with her for nine months and got her story -- if I ever spun anything in a negative way or asked, 'Was it difficult to take your medicine? was it difficult?' -- every time I said, 'Was it difficult?' she would say, 'No.' "
The book's target audience, Bush added, is young adults and teens, to "shed a light on how kids live around the world ... so that we become a global community, and also ways that kids can give back to Ana and other kids like her around the world."
When Smith noted that, "There are messages in this book, and a lot of talk about HIV, and especially about the use of condoms and safe sex," then asked if that "smacks up against some of the doctrines of what you were brought up with or what the Republican Party espouses," Bush interjected with a loud, "No!," then observed, "I'm not sure what the Republican party -- I don't know. But, no, it's not against what I was brought up with. I think all parents agree that kids need to be educated and given access to information so that kids can stay safe and healthy. I mean, everyone wants their kids to be healthy and safe."
As the tour began, reporters observed, Bush appeared far different than the college student America knew during her father's early years in the White House. The young woman who was famously cited for underage drinking and once photographed sticking her tongue out is gone -- replaced with an author who is passionate about her writing project.
If her work as a writer makes people realize she's more than a social butterfly, Bush, who also has worked as an elementary school teacher, is fine with that.
"The people that know me and love me, my students and colleagues, never had that perception of me," she told The Associated Press.
While her sister, Barbara, who works at the Cooper-Hewitt National Design Museum in New York, maintains a low profile, Jenna has begun to reveal her devotion to education and helping the underprivileged. She said she never had a reason to interact with the media until she had something important to say -- and now she does.
"I didn't have something that I was passionate about," she said.
Jenna Bush said the book came together quickly. She saw the potential in the teenager as soon as she saw her last fall at a community meeting for women and children living with HIV and AIDS. (Ana's name was changed to protect her privacy, and Bush does not reveal which country she lives in beyond saying it's in Central America.)
Bush began meeting with Ana several times a week, speaking with her -- entirely in Spanish -- about her difficult upbringing.
By the time Bush went home for the holidays last December, she had written several sample chapters and began shopping around her book proposal. She wrote most of "Ana's Story" between January and April, working with editors at HarperCollins over e-mail.
The book runs more than 300 pages, but it's written in simple language directed at teenage readers. The chapters are short, and the book includes dozens of color photographs taken by Bush's close friend, Mia Baxter, who also interned with UNICEF.
Bush said she started by writing longer, more conventional chapters, but "it just really was too much. It was too heavy, and I thought kids would find it really grueling and not at all optimistic or fun to read."
Bush says she hopes to return to teaching.
Another part of Bush's maturation: getting engaged in August to her longtime boyfriend, Henry Hager.
Bush says wedding plans are on hold during the book tour.
Hager proposed on the top of Cadillac Mountain in Maine, which Smith described as "this rocky, austere, wind-swept, formidable environment. That's not exactly romantic, is it?"
"Well," Bush responded, "for us, it's what we enjoy doing the most! People probably think we're crazy. We camped out -- the first thing we did when we were engaged was take coin showers. I think he thought, 'This is a pretty cool girl!' "
Hager asked President Bush for his daughter's hand in marriage.
"I think my father knew why he was coming," Jenna said to Smith, "so, I think my father probably made him feel completely uncomfortable, knowing him, cracking some joke! But they won't really tell me what happened. I know my father called my mom in, because he wanted it to be a joint conversation, which I think, as a woman, was a good decision."
"I'd bet there were tears all around," Smith remarked.
"Probably," Jenna replied.
To read an excerpt of "Ana's Story," click here.
All profits from the book will go to UNICEF. For more from the organization on the book, and to donate to UNICEF, click here.