It was a wintry Saturday night in Milwaukee, and 23-year-old Becky Marzo was out with friends at a local dance club, drinking, dancing, playing darts. Around midnight, Becky's cell phone rang. It was Carl Rodgers II, her live-in boyfriend, wanting to know when she was coming home. "I'm not ready to leave," she told him. A few minutes later, he called again, upset. They argued, and Becky hung up. He called again — and then again.

"Just turn the phone off," her friend Kristina Randall finally said.

At 2 in the morning, Kristina drove Becky home and waited at the curb for the sign that all was well. "She turned on the light and waved out the window," Kristina says.

And then she was gone.

Becky's mother, Karren Kraemer, sits at her dining-room table in jeans and a sweatshirt. The suburban home, in a cul-de-sac near the town of Oconomowoc, WI, about 35 miles west of Milwaukee, is warm and bright, but worry lines crease the 47-year-old mother's face.

"I was getting ready to go to work," Karren says, remembering the chilly day in January 2004 when her niece called to say that Becky had disappeared. "She said, 'Auntie Karren, I don't know what's going on, but something's happened to Becky.'" A wave of dread swept over Karren; she frantically dialed her daughter's cell but didn't get an answer — just Becky's voice mail, her greeting backed by Whitney Houston's "I Will Always Love You."

"I told my husband I thought something happened," Karren says, clenching her hands. "I'd been having dreams about Becky. So when my niece called, I thought right away that Becky was dead." Fueling her fear was the fact that Karren and her husband, Dave, hadn't spoken to their daughter in eight months, following a string of arguments they'd had with her about Carl. They knew he was abusive — they'd seen the bruises — but their daughter had refused to leave him.

"She would defend him and say, 'It was an accident,'" Karren says. "But we had heard the excuses long enough. We decided to try tough love and told her she couldn't come home again until she broke up with him." Karren stares out the window. "There are some things parents will never forgive themselves for," she says. "And that's one of them."

Karren called the police and said that none of Becky's friends or colleagues had heard from her since the night of December 13, 2003. "But they said Becky had the right to go missing," and didn't open an investigation, she says.

Karren knew that Becky wouldn't just vanish on her own. She was right on the verge of completing an accounting degree, while holding down a job at Target. "She had never missed a day at work," Karren says. "She wanted to be an accountant, have kids, the whole white-picket-fence thing." So Karren hired a private investigator, continued trying to call Becky, and kept after the police. Time and again, she says, the officers dismissed her concerns, despite the fact that Becky had once filed a complaint against Carl.

Finally, Karren drove to a Milwaukee precinct station. "I'm not leaving until you file a report," she insisted. As she waited, officers brought Carl in for questioning — with Karren in the same room. She was stunned. "I know you killed Becky!" she told him. Carl didn't blink. Police classified Becky as a missing person, but didn't open a homicide investigation since there was no evidence of a crime.

It's not unusual for a case like Becky's to be sidelined by police. Hundreds of thousands of missing-person complaints are filed each year in the U.S., and, unlike the case of, say, Natalee Holloway — the American teen who famously disappeared in Aruba in 2005 — most cases don't get much notice. If a family does persuade police to open a homicide investigation, the case can drag on for months, even years, without a resolution. Most, in fact, are never solved, and it falls to the families to do the legwork.

That was certainly the case for Karren Kraemer, who, with hardly any information to go on, became a mother on an extreme mission — channeling her sorrow, anger, and guilt into an all-consuming drive to find her daughter.

Karren's crusade began with flyers; she posted hundreds of them around Milwaukee, on lampposts and telephone poles in Carl's neighborhood, in the parking lot where he worked, along the street where his parents lived. "Please help us find Becky," the flyers implored, showing her smiling, round face framed by blonde hair, her vibrant blue eyes behind wire-rim glasses. Listed on the flyers were Becky's identifying features: 5-foot-3, 130 pounds, double-pierced ears, a tattoo on her back of a heart pricked by a red rose.

Posting the flyers became an obsession for Karren: She would get out of bed in the middle of the night, fill a thermos with strong coffee, and drive from her rural home to paper the town in the predawn hours, often in tears. Sometimes she would talk to people on the street, even vagrants: "There were some bad neighborhoods, but I can't remember ever being scared. I mean, what kind of person would hurt a mother who's trying to find her daughter?"

As she made her rounds, memories of Becky haunted her. "Becky was bubbly," Karren says, pointing to photos in the front hallway. "She was petite and brainy, but naive. And she was such a trouper. She always brought home the underdogs from school — she felt that if she could only befriend them, their lives would change." Becky volunteered in the D.A.R.E. antidrug program in school and played clarinet; on a band trip to New York, she gave her money to homeless people in Central Park. "She thought she could fix the world," Karren recalls.

Soon Karren ratcheted up her campaign even more, quitting her six-figure job as a manager at Kinko's to take a lower-paying job at Target, in the hope of ingratiating herself with Becky's former colleagues to gain information. "They told me Becky would come to work with bruises on her cheeks," she says. But they hadn't heard from her since the day she'd vanished.

Karren then sent around a feel-good video of Becky to local news stations, showing a sentimental young woman who collected Winnie the Pooh trinkets, loved country music, and was addicted to Yahtzee. Karren also called on psychics, following their leads to a set of railroad tracks and a river where they believed her daughter might be buried. She even enlisted "cadaver dogs" to search for a body. "If a psychic tells me there's a chance that Becky is down at the bottom of a river, I want to jump in and find her," she says. "You try anything."

Karren began to stalk Carl as well, reporting any suspicious move he made to the police. "I sat outside the house," she says. On the hood of his parked car, she would leave little calling cards with an illustration of Pooh, a reminder that she was always nearby. "I wanted to keep the fire burning under him," she says, with anger in her voice. "I wanted him to watch me hang flyers. I wanted him to watch me knock on doors. I wanted him to know he wasn't going to get away with it." Yet she also kept her distance, never confronting him face-to-face. And she continued to ask police to look into Carl's involvement, to no avail. "Right now, Becky is on the bottom of the workload," snapped one detective. Karren was livid. "You owe it to me to find my baby!" she said, sobbing.

In December 2004, a year after Becky's disappearance, Karren tried yet another approach. "I brought police the video of Becky," she says. "I went down to the precinct with a bag of peanuts, cookies, hot chocolate. And they sat down and watched the video." Finally, thanks to her perseverance, investigators began pursuing Becky's disappearance as a possible homicide, questioning Carl's friends and family and searching his house. But the proof fell short. There simply wasn't enough evidence to charge Carl with a crime.

Karren's hope began to fade. Becky's credit cards showed no activity; her driver's license had expired; she'd left behind an uncashed paycheck for $500. Karren struggled to accept the fact that her daughter was really gone. "I wouldn't let anybody go in her bedroom," she says. "I didn't change a thing. We held on to all her clothes and photo albums."

Still, she believed there was enough circumstantial evidence to find Carl guilty. So she kept digging. She discovered that Carl's uncle, a former cop, owned a funeral home not far from Carl's house — and that his car and Carl's had been parked outside the funeral home at 4 a.m. on the day Becky had gone missing. (Records of parking tickets had confirmed this.) Karren convinced a district attorney to approve the exhumation of two graves in a cemetery south of Milwaukee — burials performed by Carl's uncle days after Becky's disappearance. But still, no luck.

Karren's punishing crusade took its toll. Her marriage suffered as Dave grew withdrawn, declining to participate in his wife's increasingly driven campaign. Her health deteriorated as well. "I got very sick," she says. "I had an erratic heart rate and had to have surgery for that. I had stress fractures in both feet because I walked so much. It was all stress," she adds, tears welling in her eyes. "Becky had so much more to give. And this guy took so much away."

Born in Texas and raised in Milwaukee, Karren met her husband, a maintenance engineer and avid sportsman, when she was 17. They married and had five children, raising them in the Milwaukee suburb of Oak Creek. "We were what you'd consider an average family," Karren says, recalling the days when her children were young. "We were strict parents. When the streetlights came on, the kids had to come home."

Karen raised the kids while studying business management and criminal justice at the University of Wisconsin in Milwaukee. For years, she worked as a police dispatcher, which is where she developed a keen eye for investigative work. In 2000, Karren and Dave moved their family to Oconomowoc, where they live today in a three-bedroom home surrounded by flowerbeds, the garage crowded with bicycles and a riding lawn mower.

Becky had some health issues when she was young — she was treated for depression as a teenager, and suffered hearing loss that required several surgeries — yet her health didn't diminish her playfulness. "Becky was real fun," laughs Karren, grabbing a bottle of water from her refrigerator. "I remember when she was maybe 16 or 17, we went to the grocery store together, and she picked up a package of Depends, then yelled to me down the aisle: 'Hey Mom, what size diapers do you wear?'"

Becky married young, at age 19, taking the last name of her groom, a less-than-ambitious guy named Mike Marzo. But the marriage soon fell apart. She was 20 and very impressionable when she met Carl, in February 2001. He was 12 years older and a charmer, a handsome man who raced high-performance automobiles and rode a red motorcycle. Six months after they met, Becky moved into his place.

"We started noticing pinch marks on her arms," Karren recalls. "And her behavior changed. Whenever she came home, we would get into an argument and then she'd cry. I said, 'This is crazy. We don't know why you're staying with him. You don't have to.'"

Karren and Dave persuaded their daughter to move back home with them around Christmas in 2002. Carl was furious. He called Becky repeatedly. One time Karren intercepted the call. "How could you hurt her like that?" she yelled at him. His reply? "She fell."

Eventually, like so many victims of domestic violence, Becky gave in to Carl. "Don't you understand? I have no choice," she said to her father. "I have to go back."

A few months went by before Becky finally called the police, in April 2003. Carl had broken her nose, bruised her ribs, and torn out chunks of her hair. He was arrested and charged with battery. "At this point we're begging her to break up with him," Karren says. But Becky wouldn't budge. In what they saw as a last resort, Karren and Dave pursued their "tough love" approach, and told her to leave him or leave them, essentially.

So Becky took off for Florida, and Karren tracked her down by phone. "But she just wanted me to leave her alone," she says, her eyes downcast. "That was the last time I talked to her."

Soon after, Becky returned to Milwaukee and stayed with a friend. A day or two later, she abruptly moved back in with Carl and recanted her allegations. "I can tell you I probably cried every day for a month after I found out," Karren says. "I had a premonition: I just knew that this man was going to kill her...if only I could go back in time."

Months passed. On December 10, 2003, a judge formally dismissed the battery charges against Carl. Three days later, Becky disappeared.

Amid the investigation into Becky's disappearance, Karren discovered a new calling. Last year, she cofounded Broken Wings Network, an advocacy group for families of missing persons and domestic-violence victims; she also speaks about domestic violence at Wisconsin high schools and correctional facilities. Debbie Culberson, who started Broken Wings with Karren, also had a daughter who went missing, after breaking off a brutal relationship 12 years ago. "We've dug up barns; we've drained ponds," says Debbie, 54, over the phone, her voice strained by grief. "You picture yourself holding your daughter, her physical body, in your arms for all those years. Just knowing where that body is...that's what Karren and I don't have."

The two have found solace in their shared cause. But solace isn't all Karren is looking for. She needs resolution. Justice.

And there was certainly a measure of it in the shocking phone call she received from police on October 5, 2007: Carl, they said, had been found dead inside his car in his garage — a victim of probable carbon-monoxide poisoning. A month earlier, he had been charged with raping his girlfriend; a trial had been set for January 23. He'd left a suicide note in his kitchen: "I never killed anybody," it read. "I never raped anybody. I'm just tired of all this."

For Karren, it meant she would never again have to lay eyes on the man she believes killed her daughter, or picture him enjoying his life — getting on with it. But it also meant that Carl would take the knowledge of Becky's whereabouts with him to the grave. Still, Karren says, "I'm not going to let him win. I will find her."

She doesn't blame herself for Carl's suicide. "I think he did it because he felt it was the final control over what would happen to him," she says. "I'm past the point of hatred, but I haven't forgiven him. Forgiveness is a very personal thing." For his part, Carl's stepfather, Jeffrey Stemper, says, "This woman had been harassing him [for years]. No evidence has ever been shown that he did this crime." A huge portion of Karren's life now remains on hold. She has cashed out her 401K to pay for her ongoing investigation, and her marriage is in disarray. "Dave and I argue every day," she admits. "I'm just not who I was four years ago."

Since then, she has had a recurring dream: Becky standing before her, holding her hand out to Karren, crying, and asking her mother to find her.

So Karren's search goes on — along with the police investigation. Says Detective Vickie Hall, "If I were a missing person, I would like to have Karren Kraemer looking for me."

"I'm at the point where I'll do anything to find Becky," Karren says. "Until you can bury your child, you really don't have that closure. I want to say good-bye."

Kurt Chandler is a senior editor at Milwaukee Magazine. His work has appeared in The New York Times and The Advocate and on Salon.com. His latest book is Shaving Lessons: A Memoir of Father and Son (Chronicle Books).

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