CALEDONIA, Mich. (AP) -- A couple sat by their daughter's hospital bedside for weeks after an auto accident until she came out of a coma and they realized she was not their daughter after all, but another blond-haired young woman injured in the wreck. Their own daughter, it turned out, was dead and buried.

In a tragic mix-up, one family had been incorrectly told their daughter had died in the April 26 crash in Indiana, and another was erroneously informed their daughter was in a coma.

The two young women - both students at Indiana's Taylor University - looked remarkably alike, and the one in a coma suffered facial swelling, broken bones and cuts and bruises, and was in a neck brace.

The family of Laura VanRyn, 22, disclosed the mix-up Wednesday on a Web log that they had used to record detailed updates on the young woman's recovery.

"Our hearts are aching as we have learned that the young woman we have been taking care of over the past five weeks has not been our dear Laura, but instead a fellow Taylor student of hers, Whitney Cerak," the VanRyns said on the blog.

Cerak's grandfather, Emil Frank, said news of his granddaughter's survival was a shock. "I still can't get over it. It's like a fairy tale," he said.

Coroner Ron Mowery, whose office handled the case, apologized for the mistake. He said acquaintances of the students had identified the survivor as VanRyn, but no scientific tests were conducted to verify the IDs.

"This tragedy unfolded like we could never have imagined," he said.

The VanRyns said that as the young woman began regaining consciousness at a rehabilitation center in Grand Rapids, Mich., she said things that made them question her identity.

As recently as Monday, the VanRyns reported: "While certain things seem to be coming back to her, she still has times where she'll say things that don't make much sense."

The coroner said that VanRyn's boyfriend raised initial questions about her identity. Then her father became suspicious when she referred to him by a pet name he didn't recognize.

"He started asking questions and the process evolved to where she actually came to and suggested who she was and wrote her name," Mowery said.

In a statement, the two families said they took their concerns to hospital officials, and dental records confirmed that the injured woman was Whitney Cerak.

"Both families understand how this could have happened," said Bruce Rossman, a spokesman for Spectrum Health, which operated the rehab center.

Frank, a retired minister in Portland, Maine, said his granddaughter's parents declined to look at the body before the funeral. "They wanted to remember her the way she was," he said.

An official at Taylor University, an evangelical Christian college in Upland, Ind., about 60 miles northeast of Indianapolis, said the Grant County coroner had notified the school of the error.

"We rejoice with the Ceraks. We grieve with the VanRyns," said Taylor spokesman Jim Garringer.

The VanRyns, who are from Caledonia, Mich., said their daughter and Cerak, 18, of Gaylord, Mich., bore an "uncanny resemblance."

The coroner described an accident scene strewn with purses and wallets.

"I can't stress enough that we did everything we knew to do under those circumstances, and trusted the same processes and the same policies that we always do," Mowery said.

Four Taylor students and an employee were killed when their van was struck by a tractor-trailer that had drifted across a highway median. Those in the van worked for Taylor's dining services and were preparing for a banquet for the inauguration of a new president of the 1,850-student school.

Most of the crash victims had funerals with closed caskets. A month ago, an overflow crowd of more than 1,400 people turned out for what they thought was Cerak's funeral in Gaylord, Mich.

Joe Sereno, associate pastor at Gaylord Evangelical Free Church, said the casket was closed both for visitation and for the funeral.

"We did everything you usually do," Sereno said. "We had a memorial service at the church. The family did a private burial the next day. Everybody thought it was Whitney."

The VanRyn family used the blog to provide progress reports on the young woman, reporting, example, that her hair was in pigtails or braids, that she managed to feed herself some applesauce, that she played a game of "Connect Four" with one of the therapists and did quite well, and that she performed an exercise in which her therapist gave her a word and she had to supply the word's opposite.

Calls to the VanRyns and Ceraks were not immediately returned, and a young man outside the VanRyns' home declined to comment to a reporter. An attorney for 'the Cerak family did not return a call either.

Prosecutors are weighing criminal charges against the truck driver, saying he may having fallen asleep at the wheel.

A memorial service for VanRyn is scheduled Sunday in Grand Rapids.