News of Sunday’s shooting at a spa in Wisconsin brought back painful memories for Lois Robison, more than 1,000 miles away in Burleson, Texas.

Robison’s son, Larry, was executed in 2000 for the brutal murders of five people near Ft. Worth, Texas, in 1982. Every time it happens again, every time a gunman takes to a mall or a Sikh temple or a school playground, bent on rampage, Robison remembers her own son.

This past week, it was the shooting at the Azana Spa in Brookfield, Wis., that triggered those flashbacks. There, Radcliffe Haughton Jr. reportedly shot seven women, three of them fatally, including his wife, before turning the gun on himself.

It didn’t take television crews long to reach the man’s distraught father, Radcliffe Haughton Sr., the following day. “All I can say is, I want to apologize to the people of Milwaukee who have been hurt,” Haughton Sr. told a reporter on Monday. “He did not give me any hint of what he would do.”

He did not give me any hint of what he would do.

Haughton Sr. appeared to be answering an implied question, one that’s asked either directly or indirectly of parents and other relatives every time such a tragedy unfolds—“Did you see this coming? Why didn’t you stop it?” It’s why, when Arlene Holmes told a reporter “You have the right person,” after her son allegedly went on a shooting rampage in Aurora, Colo., last summer, many assumed she was saying, “I knew it was him.” Holmes later clarified she was talking about herself, not her son.

Susan Klebold, mother of Columbine shooter Dylan Klebold, took 3,800 words to answer the question in a 2009 piece she penned for O Magazine titled, fittingly, “I will never know why.” The stepmother of Wade Michael Page, the shooter in the August killings at a Sikh temple in Oak Creek, Wis., told The Milwaukee Journal-Sentinel that she had “no idea” why the child who grew up “precious” became a mass murderer.

These are unfair queries, says Renny Cushing, executive director of the Boston nonprofit Murder Victims’ Families for Human Rights. Cushing’s own father, Robert, was murdered in 1988, and Renny has dedicated his life to opposing the death penalty. He has worked with many relatives of murder victims and of killers over the years. Both sides grieve, but in different ways, he says.

“Being the family member of a murderer is incredibly isolating,” Cushing says. “There’s a shame attached to it, a stigma, so they remain silent about their loved one. People will impute responsibility on them for the actions of the family member. Society’s fear gets projected upon you, and you end up being pretty isolated.”

Lois Robison knows that all too well. She knew the day she found out her son had gone on a shooting rampage, she said in the fragile Texas drawl of a 79-year-old woman. That day, she recalls, she turned to her husband and said, “Now our whole lives will be different.”

She was right. Robison had talked to her son Larry just the night before, she said. He was at his sister’s house, and something was wrong. Mom was trying to talk her son into coming over, to her home in Burleson. Larry said he couldn’t.

“The next morning, I woke up and found out he was the one who killed all those people,” she said.

In a psychotic rage, then 24-year-old Larry Robison had killed five people, including his former roommate, 31-year-old Ricky Lee Bryant, decapitating and sexually mutilating Bryant’s body. He also killed another man, two women, and an 11-year-old boy, their bodies discovered in two remote cottages on the shore of Lake Worth, Texas.

In the shock of that initial moment, Lois’s first reaction was denial. Her son had been diagnosed with paranoid schizophrenia when he was 21, a condition that explained a host of jarring behavior throughout his adolescent years. He once ran naked through the gymnasium during a basketball game. He once ran away from home, she said, and when she found him, he was tearing through the streets of Burleson, “running like a tracked animal,” she said. “He was just scared to death. I don’t know what he was running from.”

But none of this was violent, never directed at anyone, never an obvious precursor of something horrible.

“He was the most peace-loving person in the world,” she said. So when she first heard the news, “I thought, ‘Surely he couldn’t do that. He’s too good-hearted. Too kind.’”

Mothers often describe their sons that way, even after they’ve done horrible things. Robison did that, too, to the reporters who showed up at her doorstep in 1982, wanting insight.

“On that particular occasion, he was acting like a monster. I admit that,” she said. “But he wasn’t a monster. Inside, he was very kind and loving and understanding.”

Then Robison took it a step further. She went on a crusade. She had fought for years, trying to get help for her son. Again and again, she had him institutionalized, but without a lifelong commitment, a declaration that required a judge’s order, Texas allowed Larry locked up for only a maximum of 30 days. While contained and medicated, he behaved just fine. When released back out into the world again, he went off the drugs that kept him relatively sane, and the wheels came off.

“Back then, they always blamed mental illness in boys on the mother,” she said. “It was the mother’s fault.”

One counselor asked her to get on her knees during a therapy session, Robison said, and “beg his pardon for whatever I had done.” Robison refused. She didn’t accept that blame.

After the killings, Robison spoke to any reporter who would listen, often to the dismay of the families of her son’s victims. One niece of a victim wrote her a letter, the gist of which was, “Lois Robison, shut up,” she said. But Robison didn’t shut up. Her son was “not a monster,” she said. “He was mentally ill.” She didn’t feel guilty, she said. She knew it wasn’t her fault. She had tried many times to have her son committed, she explained to the press. But because he’d never done anything violent, she couldn’t get anyone to listen, she said.

“You wait until they’re already violent, then they give you the treatment,” she said. “But that doesn’t work. After you’ve already been violent, you go to Death Row.”

Robison kept her job as an elementary schoolteacher, despite that some parents tried to pull their children from her class. Her principal defended her, she said, telling those parents, “Come back to me at midterm. If you want your child in another class, I’ll do it, but I’m not doing it right now.”

Robison eventually joined forces with Amnesty International, dedicating the rest of her life to speaking out against the death penalty. She spoke at churches, in town-hall meetings and at schools. “It was the only thing that saved my sanity,” she said.

She continued to visit her son for the 17 years he sat on Death Row. She learned that the other inmates called him “lovable Larry.” She filled him in on her life, and that of his six brothers and sisters. And one day, when Larry’s 13-year-old daughter wanted to know the truth about her dad, Robison got in the car with her and drove the girl to the Texas State Penitentiary, in Huntsville. When Larry laid eyes on his daughter, Lois said, “it was the happiest I think I had ever seen him in his life.”

This all comes flooding back, every time another mass killing shakes America’s conscience. Robison remembers her own fight to convince people that all of these killers are mentally ill, and they all needed help, sooner: “Why can’t we take care of these people, before they commit a horrendous crime?”

For the parents of mass killers, she has this advice: “Love your child. They need you. So love them. They’re not monsters. There’s a reason why this happened, and it’s not because they’re monsters or just mean. They’re sick. Love them. They need your love.”