Oprah with Christine McFadden and baby daughters
When Christine McFadden, a veterinarian in Merced, California, went out for her early-morning walk on March 26, 2002, her four children were still sleeping. Melanie, 17, Stanley, 15, and Stuart, 14, were the kids from her first marriage; 5-year-old Michelle was from her second marriage, to a former sheriff's deputy named John Hogan.

Christine had divorced Hogan in 2001 but had made room for him in Michelle's life. And so while it was unusual, upon returning home that morning, to see his truck parked in the driveway, she wasn't alarmed. Having to deal with Hogan would be irritating, but Christine was used to that. Then she went inside and came upon Melanie, lying dead on the hallway floor.

While Christine was out, Hogan had shot and killed all four children with a .40-caliber handgun, then shot himself in the head.

"My whole life—it's gone," Christine told me when she appeared on the show two years after the murders. "There will be no grandchildren. I will never see my daughters walk down the aisle, never see my sons make any great plays. There really doesn't seem to be a lot of need for me in the world."

Three years later, at 49, Christine has emerged from that bleak place. Last April she married Gerald Corman, a family law judge. And on January 26, she gave birth to their twin daughters, Nicole and Claire. The decision to have more children wasn't one Christine made lightly, but it seems to have been the right one: Around the girls, she is joyous, doting, engaged—altogether a changed woman, ready to move forward.

Yet there remains an irresistible pull toward the past. The new family lives in Christine's Merced home—the house where Melanie, Stan, Stu, and Michelle lived and died—and for all the signs of new beginnings, loss is reflected everywhere. The dining room table and the refrigerator are covered with family photos, every one of which has the power to bring Christine to tears. Melanie's ballet slippers still hang on the door to her bedroom, which has sat practically untouched since 2002; the murder investigators' bright yellow "caution" tape is still attached to her bedpost.

When Christine first appeared on the show—beyond stunned, beyond hope—I told her I believed that her story would save lives. I told her that among all the people watching that day, there would be some who'd decided it was going to be their last day—but that seeing her would change their minds. Sure enough, out of the thousands of letters we got after the show, 16 were from people who'd been planning to commit suicide—and then didn't. I later invited Christine back to the show to meet three of these women, one of whom had told me, "I get up because she has the strength to."

That strength is why I flew to Merced when the twins were just four weeks old—to talk to Christine again, and to hear what carried her through.

Start reading Oprah's interview with Christine McFadden

Note: This interview appeared in the May 2007 issue of O, The Oprah Magazine.