A young woman died at a luxury resort in Mexico more than six months ago — and her family still doesn’t have answers about how it happened. Abbey Conney, 20, and her brother, Austin Conner, 22, were at the Iberostar Paraiso del Mar resort with their parents in January for just a few hours when their vacation ended tragically.

The last thing Austin remembered was taking a mysterious shot of something at a bar with a seemingly friendly couple. His next memory was waking up inside an ambulance.

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The brother and sister were found floating face down in the resort’s pool shortly after. After being pulled out of the pool, Austin was taken to the hospital and treated for a concussion. He survived.

Abbey did not. The 22-year-old University of Wisconsin-Whitewater student was unresponsive and in a coma with a cracked collarbone. With a lack of oxygen to the brain and cerebral inflammation, Abbey’s life support was withdrawn Jan. 12. Her death was ruled an “accidental drowning.”

Austin admitted the two were drinking, but not nearly enough to have caused them to be face down in a pool with no ability to function.

“I’ve been in college for five years and had my fair share of drinks before,” the 6 foot 2, 155-pound student told the Milwaukee Journal Sentinel Tuesday. “No way in hell I’m putting my face down in a pool and going to sleep.”

Austin and Abbey were on their way to meet their mother and stepfather for dinner that day and had no intention of getting excessively drunk.

“Somebody just had to slip them some type of drug,” their father, Bill Conner, told the Journal-Sentinel.

And the investigation, or lack thereof, into Abbey’s death and Austin’s injuries proved less than satisfying for the family. The police department in Mexico told an attorney who was probing the incident that they had done a “limited investigation” and interviewed three of the hotel’s employees, though it did not say when.

A blood test showed no trace of any opioids, benzodiazepines (associated with date rape drugs) or cocaine. The test did not, however, test for all types of drugs.

“It’s all too convenient,” the family’s attorney, Florentino Ramirez, said of the police report. “If it was an accident, where was everybody? It just doesn’t make sense. There are too many open ends.”

Two blog posts uncovered by the Journal-Sentinel detailed similar incidents recorded by other travelers at the Iberostar’s sister resorts in Playa del Carmen.

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Abbey and Austin’s family is still working to uncover what, exactly, happened to their children that day.

“I still can’t believe this happened,” said Conner. “I’m still waiting for my daughter to walk through the door.”