And she flashed her famously acid wit. I started patting one of the family dogs in the very casual family room of the big house, which the elder Bushes used at Kennebunkport. “This one will bite anyone who tries to hug me,” she warned. “But I haven’t asked your permission to hug you,” I replied, a little startled. (What stranger would try to hug a Secret Service protectee before asking?) Without missing a beat, she replied, “If I don’t like you, I will let you.”

She could get serious, as well, and when she did, you sensed why hers was likely the strongest backbone of the Bush family. The day before, nine people had died in a mass shooting at a community college in Oregon. “We don’t have guns in our house because of me,” she explained. “I don’t like guns.”

At the time I was researching a history of gay men in Washington, D.C. I asked her about the role she had played in encouraging her husband to acknowledge the AIDS crisis. She had suggested that he visit an AIDS clinic during the campaign in 1988, which he did. And in her first weeks as first lady, Bush visited a young man in a hospital who was dying from AIDS. “People thought it was [an easily] communicable disease,” she recalled.

When I said she had been politically courageous, she said, “Not if you think about it. It wasn’t courage.” “But President Reagan didn’t do it,” I countered. The look she gave me signaled her disagreement with Reagan. She then started to describe the dying AIDS patient. “This man, who was a Roman Catholic, had lost his mother when he was young and had been rejected by his father.” Bush teared up as she talked about him. She then added that he had died, as did a baby stricken with AIDS, whom she had also visited. Although these visits had occurred nearly 30 years ago, they seemed to affect her as if they happened just the week before.

We ate lunch at a restaurant in nearby Goose Rocks. Barbara Bush mentioned that the person who greeted them as a friend when we all entered the dining room was gay. “I sensed that,” I said. I paused, then added, “I am gay.” Instantly, she replied with a smile, “I sensed that.”

This is not what I expected to be discussing with a 90-year-old former first lady. But talking about LGBT matters had stirred something that was evidently bothering Mrs. Bush. “Well, you know what I think about President Obama. Did you see that he just appointed a transgender person? Do we announce each time the appointment of a heterosexual?”

She said she wasn’t against the hire, she just didn't understand why the White House should make a point of a person’s sexual identity. I explained, as best I could, the sensitivity of the transgender community, because for so long the focus of the struggle for LGBTQ rights had been on the G and the L, and, respectfully, reminded her that when the White House recognizes a group it has a tremendously positive effect on not only that group’s self confidence but on how other Americans view that group’s place in our society.