Always ‘passionate’ about gay rights, the bestselling novelist felt the political becoming personal when her oldest son came out

Jodi Picoult has always used her novels to explore hot-button topics. Stem-cell research, euthanasia, the death penalty—”They’re the things that keep me up at night,” she says. Her latest novel, Sing You Home, started the same way: She decided to make one of her main characters a lesbian because “gay rights is the last set of human rights we haven’t granted in this country,” she says. “I wanted to poke this issue with a stick.”

Then, in the fall of 2008, her son Kyle—who knew nothing about his mom’s book-in-progress—came out to her. “He asked me to read his college application essay, in which he said he was gay,” she says. “I remember reading it and saying, ‘Do you want me to talk about the grammar or the content?’ He goes, ‘Both.’ I was really happy he felt comfortable enough to tell us.” But at that moment her novel took on a more personal urgency. “All of a sudden it wasn’t a theoretical journey into what it means to be gay in America,” she says. “It was this mission as a mom wanting really badly to change peoples’ minds with my book. I want the world to be a kinder place by the time Kyle gets married and has kids.”

Not that he’s faced much discrimination to date. The oldest of Picoult and her husband Tim’s three children (son Jake is 17, daughter Sammy 15), Kyle, now 19, showed a fondness for playing princess as a child that made his mother wonder, but he was never bullied for it. He had plenty of friends at high school in Hanover, N.H., got into Yale and received nothing but support from his family after they learned about his sexual orientation. “A lot of people come out to their families, and then none of them talk about it again,” Kyle says. “It wasn’t like my family would go, ‘So Kyle, what gay things did you do today?’ But it wasn’t not talked about.”

Researching her book, however, reminded Picoult that “the beautiful bubble of acceptance” Kyle enjoys isn’t available to everyone. While interviewing lesbians and Evangelical Christians—her novel features a divorced couple fighting over frozen embryos after the wife falls in love with a woman—she came face-to-face with entrenched intolerance. And on her book tour, “I meet kids who hide who they are because they know they’ll be thrown out of the house,” she says. “It breaks my heart.” She recently filmed an It Gets Better ad to help gay teens realize they’re not alone.

For his part, Kyle is more interested in enjoying college life than changing the world. “I’m not an activist type,” he says. He’s studying Egyptology and happily dating Kevin Ferreira, 20, a student at Wagner College in New York City. Still, he’s proud of his mom’s dedication to gay rights (“She does good things for people through her books”), and her crusading spirit has clearly rubbed off. In the essay that helped get him into Yale, he told a story about a 5-year-old boy he’d worked with at a summer theater program who was being teased for wearing dresses and carrying a purse. The next day, Kyle showed up in 3½-in. black patent leather pumps. “I wanted to show him it’s okay to be different,” Kyle says. “It’s okay to be yourself.”