First ladies often pick areas of policy to champion—and Bush chose literacy. She launched a literacy foundation in her name in 1989, the first year of her husband’s presidency. The goal of the Barbara Bush Foundation for Family Literacy is to ensure that every child, regardless of socioeconomic status, has access to educational opportunities to teach them reading and writing.

“If we don’t give everyone the ability to simply read and write, we aren’t giving everyone a chance to succeed,” she had said, a quote posted on her foundation’s website.

Bush often stayed out of policy debates, at least publicly, but she did advocate for the National Literacy Act of 1991, which aims to strengthen adult literacy programs and ensure universal literacy. “Literacy is where education begins. I first understood the truth of that statement by watching Barbara in her work that still continues, working her heart out for literacy,” her husband, former President George H.W. Bush, said in homage to her at the signing of the bill.

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“Literacy is her major legacy,” said Myra Gutin, a professor of communication at Rider University and the author of Barbara Bush: First Lady of Literacy. “She had been interested in literacy for years before she was First Lady and her interest continued after she left the White House.”

In addition to her two memoirs, Bush also authored two books while she was first lady, both written from the perspective of her dogs. But even after leaving public office, her commitment to improving America’s literacy continued—with initiatives like a partnership with NFL player J.J. Watt to encourage parents to read to their children—until the end of her life.

The usual narrative about Bush’s interest in literacy is that it sprang from her experiences with her son Neil, who is dyslexic. She helped him through the arduous process of learning to read, and defied the educators at his Washington, D.C. prep school who said he would be unable to graduate high school. (Neil now chairs his mother’s foundation). But Bush’s choice to champion literacy is also indicative of her persona—and legacy—as a whole, say both Gutin and James Engel, a presidential historian at Southern Methodist University.

“She very wisely chose an issue people couldn’t really object to,” said Engel. “The problem would be worse were it not for Barbara Bush’s efforts.”

Throughout her life in the political spotlight, Bush was deliberate about picking causes to publicly champion, letting her opinions be known—without generating the type of controversy that might overshadow the career objectives of her husband.

“It seems to me that the literacy initiative is pragmatic and as pragmatic as Barbara Bush [tended] to be,” said Gutin. “It made sense to her.”

Engel also said toeing this line gave her room to really assert herself when she felt something was important. Like in 1989, when, two months after her husband’s inauguration, she visited a residential home for babies infected with AIDS and publicly kissed a child and hugged an adult diagnosed with HIV, defying the conventional wisdom at the time that the disease was contagious.

“We’ve had so much trouble with all the talk about the dangers of personal contact. Here, the first lady isn’t afraid—and that’s worth more than a thousand public service announcements,” one administrator of an AIDS clinic in D.C. told the Washington Post at the time.

“She was a straight forward talker, thinker and actor,” said Engel. “She was not interested in hiding her opinion when she didn’t want it hid.”