Transcript for Family seeks answers after daughter dies at Mexico resort

We'll begin with the search for answers of a young American tourist mysteriously died at a luxury resort. Abbey Connor and her brother found unconscious in a hotel swimming pool and now major questions about foul play and gio Benitez is here with that story. Good morning. Reporter: Good morning to you. Part of the mystery here is that this all happened in an hour as the parents were getting ready for dinner and one woman is dead. Her brother barely remembers anything and the parents are fighting for answers. It was supposed to be a fun family vacation to a five-star all inclusive resort in playa del Carmen, the kind of luxury seen in this promotional video. But just hours into this Wisconsin family's trip, 20-year-old abbey Connor and her 23-year-old brother Austin ended up in a Mexico hospital abbey dying just days later. Someone needs to be held responsible. Reporter: Her biological father not on that trip speaking out by phone. It doesn't make any sense. We're lucky we didn't lose both our kids. Reporter: They had been swimming at the pool just chest high water this January at the iberostar paraiso del mar resort. Mom and dad left the pool to get ready for dinner but an hour later they didn't show up in the lobby and learned they were in an emergency room 14 miles away. The hotel reportedly told them both were found unconscious in the pool face down. Austin with a concussion and golf ball size lump on his head. Abbey with a broken collarbone brain dead and died in a hospital days later. She was healthy but for some reason she drowns in a pool waist deep. It's unbelievable. Reporter: We know their blood alcohol level was around a 0.25. Three times the league limit in their home state of Wisconsin and Austin says the last thing he remembers was taking a shot with a group by the pool. Something like a Yeager bomb. A 70 proof cocktail of Yeager Meister and an energy drink. There's so many unknowns and mystery around what happened to these two kids. That it really begs for a thorough investigation. Reporter: Mexican officials ruled this an accidental drowning but that's not enough for the family. Mexican bliss, they say, refuse to investigate further but past guests reported blacking out after drinking at the resort's bar. One woman writing online, I remember thinking I must be dying. Another guest writing his wife blacked out, became violently ill. The resort telling the family there's no surveillance video. The state department telling ABC news it is aware of this case. And ABC news has reached out to the resort for comment but we've not heard back. The family intends to keep investigating. They're sure there's more to the story. There's so many questions here, gio. I mean, robbery, kidnapping, attempt. There's got to be something. Looking at that but then they say this happened in the middle of the day. In a hotel pool. They didn't have a wallet with them. They didn't have any jewelry so the robbery doesn't make sense then the middle of the day kidnapping doesn't sort of make sense either. I know. Like I said, so many -- that family just needs some answers. We all do, thank you. We have new details about

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