When a person-child or adult-disappears, family and friends are often left with nothing but unanswered questions and unhealed wounds.

When a person-child or adult-disappears, family and friends are often left with nothing but unanswered questions and unhealed wounds. They replay moments again and again, spend hours gazing out the front window, leave lights on, pray. It's a torment that likely won't cease until they find the person they so miss, or, in many cases, not even then.

On an ordinary Friday night near Ohio State's campus, students swarmed High Street, the pulsing artery of university nightlife aglow with street lamps and neon signs. They filled rows of bars and restaurants, shaking off any last remnants of winter's hibernation. It was March 31, 2006, spring break was right around the corner and the weather was beginning to warm. Too cool for shorts, but balmy enough that long sleeves could stand in for a jacket.

That evening, Brian Shaffer, a second-year Ohio State medical student, had dinner with his father at an East Side steak house before meeting a friend at Ugly Tuna Saloona, an upstairs bar in the South Campus Gateway. He was set to depart for Miami, Florida, the following Monday for a vacation with his longtime girlfriend, also a medical student at Ohio State. She was anticipating a marriage proposal, she had told friends, and was hoping it would happen on the trip they'd planned for spring break. She had left Columbus to stay with her parents in Toledo for the weekend. When she spoke to Brian on the phone around 10 p.m., she had no idea it would be the last time she would ever talk to her boyfriend.

Later, a friend would tell Brian's father and the police he and Brian were separated in the crowded bar and, although he'd called Brian repeatedly when he was ready to leave, he never found him. Video surveillance backs this, and it also shows Brian entering the bar but never exiting.

The handsome, dark-haired 27-year-old student was gone. His car was still where he'd parked it near his off-campus apartment, which was tidy and virtually undisturbed. None of the belongings he carried with him that night were ever found-no keys, no wallet, no clothes or shoes. Here one day, gone the next.

The story quickly gained national attention. "Dateline NBC" and Fox News aired national reports, and the case has since been featured in TV specials on mysterious disappearances. It gripped Columbus especially. Paper fliers covered telephone poles and message boards as volunteers searched for any clues as to what happened to Brian. His friends and family were left to endure the aftermath. Among them, a grief-stricken father, a scared younger brother and a devastated girlfriend, all seeking answers and waiting for Brian to come home.

More than eight years later, they're still waiting.

So, too, are the friends and family of the estimated 90,000 people who are missing in the U.S. today, according to the National Missing and Unidentified Persons System. They share a pain that only those who have experienced it truly understand. It's a heartache that never eases, a wound that never heals. Often, there's no funeral to attend, no body to lay to rest. For those whose son or daughter, brother or sister, child or parent, friend or spouse has gone missing, grief and hope intertwine and spin a complicated web of emotions, each competing for the lead role. Over months, years and even decades, they wait and wonder and pray, dreaming of the day their endless questions will be answered. Some continue the hunt and others attempt to move on, but none forget.

Brian's unsolved disappearance continues to baffle detectives on the Columbus Division of Police's missing persons unit. Information on the case fills four boxes; that's more than most detailed homicide investigations. Detective Andre Edwards has sifted through the contents of these boxes countless times, searching for something, anything, that could have been overlooked. The sheer lack of leads is part of what makes this one so maddening.

Years ago, when detectives began to piece together the chain of events on the night Brian went missing, Edwards spent hours upon hours scrutinizing the surveillance video that captured the image of Brian just before he vanished. He watched him enter the bar, step outside to talk with friends and re-enter a few minutes later. He rewound the tape over and over again, pausing as each patron exited, waiting for a glimpse of Brian. Edwards can recount it like the scene of a favorite movie.

Grainy footage shows Brian standing at the top of the escalator outside the Ugly Tuna Saloona a little after 1 a.m. on the morning of April 1, 2006, talking to two women whom his friend, Clint Florence, knew from Ohio State. After the two women leave, he walks back inside the bar. Florence and another woman they were with told police later they had seen Brian after he'd returned to the bar and told him they were getting ready to leave. Then they lost track of him. After scanning the bar for Brian, calling him repeatedly and waiting for him outside, they left, assuming he had gone home without telling them.

Edwards saw it all on the video as Brian's friends said it happened. He watched it so many times he could confirm that every person who left the bar had also entered-he'd rewind the tape just to make sure. He wanted to rule out the possibility Brian had changed clothes or disguised himself in some way.

"I can say with 100-percent certainty that Brian Shaffer did not go back down that escalator," says Edwards, who now works on the division's physical abuse unit. Aside from leaping over the second-story balcony and landing on an awning below, there was only one other way Brian could have left the bar undetected by security cameras. Part of the building was still under construction, and a construction elevator outside surveillance range could have been taken down to the first floor. Several theories of what happened to Brian that night exist, including the possibility he left the bar with the intention of never being found. Some said the stress of medical school, coupled with the death of his mother, who had died of cancer less than a month before he went missing, was enough to drive him away.

"We have three different theories," says Sgt. Denise Reffitt of the Columbus police missing persons unit, "but none that we can discuss."

In the weeks that followed, officers canvassed the area for clues and led cadaver dogs through the building. They tracked Brian's cell phone and bank accounts and interviewed friends and family members. The only solid lead they had turned out to be a dead end. Eight years later, police still receive at least two Crime Stoppers tips on Brian each month, but nothing has come of any of them.

Last year, the Columbus police missing persons unit handled more than 4,500 cases, excluding roughly 1,200 cases in which someone had violated a child-custody agreement. Cases rarely stretch from one year to the next; most people are found, one way or another. Still, the unit has its share of cold missing-person cases. One dates back to the 1980s.

"These cases become a part of you," Reffitt says. "They keep you up at night. You think about them all the time."

Even today, Edwards finds himself doing double-takes in crowds or while watching TV.

"I'm constantly looking for Brian," he says. "When I go on vacation now, when I see commercials, if there's anybody that resembles Brian, it catches my eye." While directing traffic at an Ohio State home football game last year, Edwards swore he saw Brian walking down Lane Avenue. As it turns out, it was actually Brian's brother, Derrek, who still lives in Columbus. Their father died tragically in a storm in 2008. Edwards says he rarely hears from Derrek. (Brian's family members and former girlfriend declined to be interviewed for this story.)

"Every time they get in touch with us, it stirs the memories again," adds Columbus missing-persons detective Jon Compson. "With some of these long-term cases, we may only hear from the family once every couple years, because it's a sad, dark spot in their life, and they want to move on."

But for some, there's no moving on-not until they have all the answers.

--

Christina Metzler remembers the last time she saw her sister more than 20 years ago.

It was July 3, 1991, and she was at home in Reynoldsburg. Her older sister, Diana Smith, was at the pool in their condo complex. Diana, 19 at the time, was a rebellious teenager. Though she had a bed in their childhood home, she rarely spent the night. The older she became, the less she'd visit. Christina, three years younger than her sister, didn't pay much attention to her comings and goings. She was too caught up in her own teenage drama to keep tabs on her sister.

On that summer day, their mother, a deeply religious Christian, had told Diana to come inside to get ready to go to church with their older brother and father. Diana, who rejected the family's religion, didn't want to go. So she left.

"I always thought she'd come back," says Christina, 40. She had every other time before. Diana began running away from home when she was 13, but she'd rarely be gone for more than a few weeks without checking in. "That's what I assumed back then."

Diana and Christina had been close growing up. They'd have snowball fights in the winter and walk to the local Dairy Queen for ice cream in the summer. Diana was protective of her baby sister, Christina recalls. They once had to hightail it home after Diana punched an older girl for giving Christina a dirty look. She was also creative and loved to sing and draw. Christina remembers a large sketchbook full of her drawings, pictures of animals and landscapes and other reflections of a child's imaginations. Her favorite song to sing was Amy Grant's "El Shaddai."

At home in Celina, Ohio, where she lives with her husband and youngest daughter, Christina pulls two thick, leather-bound Bibles off a shelf. They belonged to her mother before she died in 2012. Tucked between the pages inside are yellowed pieces of paper, worn from being folded and pressed over decades. A penciled outline of a bunny rabbit Diana had drawn as a child. Notes Christina had scrawled her mother and sister as an elementary student. And a short letter written in blue-inked cursive handwriting her mother had written Christina before she died. After Diana left, her mother didn't talk about it much. The letter, Christina says, is difficult to read now.

"If our Diana should come back to us, tell her that I love her and I never stopped loving her," the letter reads. "I know why she left and why she felt like she could not come home."

Her mother had also left Christina her personal diaries, which told a haunting tale of a past Christina never knew. She won't share the contents but says she now has an idea of why Diana was always running away.

"I didn't understand why she left," Christina says. "I felt that she didn't love us. I just thought she didn't care about us and didn't want to be around us."

This sense of abandonment is common among those who have had a loved one go missing, says Ken Yeager, licensed social worker and professor of psychiatry at Ohio State. So, too, is a feeling of guilt.

"A lot of times, they come to the conclusion it's their fault," he says. "If you had [someone go missing] in your life, would you not worry about something you said to them? 'Is it something I did?' " These distorted views make coping difficult.

Yeager is the director of the Ohio State medical center's Stress Trauma and Resilience (STAR) program, which offers therapy and counseling to families and caregivers who have experienced traumatic losses or life events. About two percent of those they serve have had a loved one go missing.

To help patients process these emotions in a healthy way, Yeager says therapists often use cognitive-behavioral therapy. "People see things and process things through a variety of filters. And they begin to assign meanings to these, and sometimes the meanings get distorted." The goal of therapy is to "help the person understand what those [thoughts] are about-if they're distorted, if they're accurate-and helping them to process through those." Healing involves releasing guilt or blame, he says.

Healing also requires grieving.

Someone whose loved one has gone missing experiences grief much differently than someone who is mourning death. Often, it's trickier, which Yeager attributes to not having answers.

"[It's] very different because people don't ever want to give up hope. The person is always walking that line of hope and reality. In many ways, it's similar to the [death] of a loved one, because you have a million missed moments. But there's no placing closure on it. For some people, they're just not able to walk away from that without knowing what happened."

The fear of the unknown is another complication. It's common, he says, for people to imagine the missing person in a harmful situation. "Are they homeless? Are they injured on the side of the road and no one knows they're there? Are they held captive? All of those thoughts run rampant, and there's a tremendous amount of helplessness."

Christina says images of these scenarios and more had often run through her mind over the past two decades. But she tried to remain positive and imagine her sister had found a better life somewhere else and was happy.

Now, she knows what happened. She has the answer. Still, it offers her little respite.

As her father lay dying in a cancer treatment hospital last year, he drew Christina close to him and asked of her a favor. She cries as she recounts what he said: "Can you please try to find your sister? This is something that your mom and I have wanted for a long time. I want to find her before I die."

And so she began her hunt. At first, she was reluctant. What if Diana didn't want to be found? But she knew this is what her family needed.

In April 2013, she contacted the Reynoldsburg police to report her sister missing. (She said her mother had filed a missing persons report back in the 1990s, but there was little to be done because Diana was an adult who had left on her own free will. Eventually she hired a private investigator, to no avail.)

She reached out to people who knew Diana and to members of their former church. She heard all sorts of rumors: Diana was married with a child and living in Westerville. She was living in California running a drug-rehab center. Christina looked on Facebook, searched missing-persons websites and eventually connected with a missing-persons advocate based in Cincinnati who helped her create a profile for Diana in the National Missing and Unidentified Persons System (NamUs), a free online database that contains records of unsolved missing-and unidentified-persons cases nationwide. It cross-references DNA between the two in an attempt to match missing people with unidentified remains.

More than 17,000 missing-person cases have been reported to NamUs, funded by the National Institute of Justice, since its inception in 2007. As of June, 337 unidentified human remains had been linked to missing-person cases through the database.

This is how Diana Smith was linked to a homicide that had been unsolved in California since 1991. The remains of a female who had been shot to death had been found by the side of a highway and remained unidentified until Diana's case was entered into NamUs last year. A detective with the San Bernardino police department called Christina this winter with the news.

Christina won't discuss the details or the circumstances of her sister's death. She doesn't need to. All that matters is Diana isn't coming back.

"It's just not fair," she says. "I feel like my whole family was [robbed]."

She recently wrote a heartfelt letter to Diana, something her aunt suggested might help her heal. Writing about her grief did help her mourn, she said, but knowing Diana's fate doesn't bring her any closer to finding peace.

"I know the outcome; I know where she is," she says. "But there are still a lot of unhealed wounds."

To experience a loss like this, in many ways, is like experiencing a death twice, says Kristen Santel, a licensed social worker in Columbus who specializes in trauma and grief. Not knowing still gives a person hope; knowing can take it all away. Sometimes, she says, people wish they could go back to not knowing.

"The not knowing keeps the hope alive," Santel says. "But it also requires so much emphasis on the person's possible death and the possible pain and misery. It takes away from the memory of the person's beautiful life."

For those still seeking answers, the wait is agonizing.

--

Robin Stepp thinks about her son, Cody, every day. The last time she saw him, he was an energetic, tow-headed 3-year-old with blue eyes and chubby cheeks. That was 17 years ago.

Aaron Cody Stepp was living with Robin's younger sister and mother on the South Side when he disappeared from a neighbor's yard in 1997. Robin's sister was Cody's legal guardian while Robin was serving a prison sentence for prostitution and theft. The day her sister and mother reported him missing was the day before Robin was to be released. She watched the city-wide search for her son-choppers soaring over streets, police officers and dogs scanning nearby woods-on a local news broadcast. Robin's theory, one that's backed by Columbus missing-persons detective Robin Tucker, who has been investigating the case since 2011, is Cody was handed over to another family member and could be in West Virginia or Kentucky, where Robin has relatives. Her sister failed a polygraph test shortly after Cody's disappearance, but there's no solid evidence of her involvement. To make matters worse, Robin's sister and mother have since died.

In 2012, there was a break in the case Robin was sure would lead her to her son. Investigators found a teen by the name of Aaron Cody Stepp who matched a description of Cody, based on an image of what he might look like as an adult generated from photos of him as a toddler. They traveled to Kentucky to collect the teen's DNA and compare it to Robin's. It wasn't a match.

Robin hasn't given up hope, though. Detectives are working on yet another lead.

"I hope it'll be my son we find this time," says Robin, who says she's been clean for four years. "I just want him found and brought home. It's been too many years."

Though less than 2 percent of participants in the STAR program are in this type of situation, Yeager says the community of people looking for a missing loved one is more prevalent than one might expect.

"The missing-persons population or the population of parents of murdered children-you don't think they're very big until you go to one of their groups and see that they're a lot bigger than you'd think," he says.

The STAR program offers group therapy sessions, and Yeager recommends families join other support groups as well. While there's no official network of survivors in Ohio, oftentimes support groups form organically.

Lori Davis has seen this firsthand. Davis, a web designer by trade, has been an unofficial advocate for missing people in Ohio ever since she offered to help update the website created by friends and family for Brian Shaffer, findbrianshaffer.com. Brian's father, Randy, called her soon after she reached out.

"He was trying to do anything he could to find his son," she says. Davis took over managing the website, which contains details of Brian's case and posts updates. She also created a Facebook page for Brian. A friendship formed between their families; hers would attend prayer vigils for Brian, and the Shaffers would attend her backyard cookouts. She spoke to Randy on the day he died, just hours before a tree crushed him in his backyard during a storm.

"I had promised Randy that I would never give up on Brian," she says. "I've just tried to keep that promise."

As she focused on spreading the word about Brian's case, she began to realize just how many more missing people there were in Ohio.

"I started seeing all these faces, and I thought, 'They've got a family. They might just be one person, but this is somebody's son or daughter.' They all deserve to be looked for."

So she started another Facebook page: Missing Person from Ohio, where she regularly posts information about missing children and adults throughout the state, including breaking news reports and other stories. She often receives messages and emails from parents of other missing people in Ohio, seeking help and direction. She'll tell them where to start and show them how to create a missing-person profile on NamUs and the Ohio attorney general's database. She's also seen how families connect with one another-attending each other's fundraisers and spreading the word about cases.

Sometimes, she says, she'll receive a note saying a loved one has been found. Her work is a small but thoughtful effort. It's her way of supporting suffering families and providing to them what she'd want most if ever placed in the same situation.

Says Davis, "I feel like I'm doing something that can give somebody hope."