Calico vanished in 1988 and, less than a year later, a Polaroid of a girl that looked like her was found at a Florida convenience store

In July 1989, 10 months after his teenage stepdaughter Tara Calico vanished near their home in New Mexico, a friend called John Doel with word of something strange: A photograph had surfaced in Florida showing a young woman and a boy who’d been bound and gagged — and the woman looked just like Tara.

The image, a color Polaroid in good condition discovered by a woman in a convenience store parking lot, made national news. Both apparent victims faced the camera, their mouths taped and arms pressed together behind their backs, as though tied up.

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It appeared they were in the back of a vehicle — perhaps a van — and they seemed in obvious distress.

But who were they? Were they really captives? And was the photo a clue to Calico’s fate?

The questions have lingered for nearly 30 years, ever since Calico went missing one September morning in 1988 while returning from her regular bike ride in Valencia County.

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Calico’s mom, Patty Doel, believed until her death that the photo showed her daughter. As the case remained unsolved into the age of internet-enabled amateur sleuthing, the picture gathered further notoriety under ominous headlines such as “A Teen Girl Was Kidnapped, And The Only Evidence They Found Of Her Being Alive Was A Horrifying Polaroid.”

Authorities, however, have never been sure the photo was connected to Calico’s case.

It was analyzed at least three different times — including by the FBI, who felt strongly that it likely wasn’t Calico, but could not say for certain, and by Scotland Yard in the U.K., who declared it was her.

The Valencia County Sheriff’s Office, the lead investigating agency, is not actively pursuing the image.

Instead, they and the FBI are probing local suspects in the case amid longstanding theories that Calico was taken or attacked by people in her small community. These suspicions are supported by witness reports that she was followed on her final bike ride and had been receiving “threatening” notes on her vehicle.

Still, her loved ones wonder.

“When people ask me, ‘Is that her?’ If I had to say yes or no definitively: Yes, that is her,” says Michele Doel, Calico’s stepsister.

But, Michele acknowledges, “Does it make sense? No. That’s not the story that makes sense.”

Image zoom Tara Calico circa 1987 Melinda Esquibel

A Polaroid Thrusts the Cast Into the Spotlight

Valencia sheriff’s officials first learned of the color Polaroid on July 28, 1989, when Calico’s stepfather, John Doel, called to report it.

John said a friend of his had seen it on A Current Affair after the image surfaced in Port St. Joe on Florida’s panhandle, some 1,500 miles away. Police reports show it was found a month earlier, on June 12, 1989.

The twist made more headlines around the country and was featured by Oprah Winfrey and on America’s Most Wanted, according to Valencia Sgt. Joseph Rowland, the current lead investigator.

The vehicle in the photo was identified as a van, and tips subsequently poured in about various vans, Rowland says. But answers were not as forthcoming.

Calico’s family quickly came forward, saying the girl resembled their missing daughter. Another New Mexico family felt the same about the young boy, saying they believed it was their missing son, 9-year-old Michael Henley, according to Rowland.

Michael reportedly disappeared in April 1988, while hunting with his father.

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”He looks scared, real scared, but he looks healthy and I’m grateful for that,” Michael’s mother, Marty Henley, said soon after the Polaroid was found in ’89, according to the Associated Press.

However, Michael’s remains were discovered about two years later, Rowland says. He had died of exposure.

Further investigative scrutiny has also called into question what the Polaroid truly depicts, Rowland says. For example, the young woman’s hands appear to not be tied together tightly, and her shoulders do not seem stressed as they would if her bindings were severe.

What’s more, Rowland says, “There was no redness around the tape on the mouths of the children, which would indicate that the tape was not on their mouth for an extended period of time.”

To this day, neither the boy nor girl in the photo has ever been positively identified.

Image zoom Valencia County Sheriffs office

A Mother’s Years of Hope and Grief

Patty Doel died in 2006 of complications from a series of strokes, after relocating to Florida with husband John. But her daughter was alway on her mind, her friends and family say.

She and John kept a bedroom for Calico, bringing her gifts there for passing Christmases and birthdays.

Even near the end, Patty “would see a young girl on a bicycle and would point and write down ‘Tara,’ ” her longtime friend Billie Payne recalls. “And [John would] tell her, ‘No, that’s not Tara.’ ”

Calico’s older brother Chris says the stress of his sister’s disappearance and its persistent irresolution significantly shortened his mother’s life.

“The police would send photos of every possibility, including photos of bodies, dismembered bodies, and every time mom got an envelope with the newest pictures, she had to look at them,” he tells PEOPLE. “She couldn’t not, but it tore her up every time.”

For Patty, the Florida Polaroid was proof that her daughter, though she was suffering, had survived whatever she encountered on her bike ride in 1988.

“Mom really did not want to believe she was dead, period,” Chris says. “And if a photographic evidence of a young woman alive — even though she’s in extremis — is something to latch onto.”

Following Patty’s death, Michele Doel has taken the lead in their family in keeping a spotlight on the case. She also does grassroots detective work of her own, alongside Calico’s high school friend Melinda Esquibel, the host of the podcast Vanished: The Tara Calico Investigation.

Michele remembers the moment when Patty first showed her the Polaroid all those years ago — and the goosebumps that broke out on her skin. Though she knows authorities believe they are looking in more fruitful directions than investigating the photo, and though she knows there are good reasons for this, she finds herself grappling with “what if?”

“I still look at it and it looks exactly like her — exactly like her. But it doesn’t make sense,” Michele says. “It really does not make sense.”