People with hypersomnia regularly sleep soundly for more than nine hours a night, but rarely feel refreshed, reports U.S. News & World Report.

One Friday night in August 2008, Jennie Murray went missing. Her mom had flown to Tempe, Arizona, where Murray was about to begin school at Arizona State University, but she never picked her mom up from the airport as planned.

Throughout the night, Murray didn’t answer her phone. At noon the next day, her mom reported her missing to the police.

Then, Murray woke up.