Definition: In this task, you will be presented with a passage and have to answer a question based on your understanding of the events inferred from the passage. Try to find the best answer that is most likely to fill in "_". Note that the URLs in the text have been replaced with [Link].
Input: The investigation into the deaths of a ghost-hunting couple in Nevada has determined a male roommate of the woman was fatally shot in the head in a Reno home several hours before police found the paranormal investigators in a barricaded apartment. Debra and Mark Constantino had appeared on the Travel Channel's series, 'Ghost Adventures,' including episodes shot at the Mustang Ranch brothel near Reno. They were found dead Tuesday at their adult daughter's apartment across town in Sparks after a two-hour standoff that ended when a SWAT team burst through the door to find their bodies. About seven hours earlier, Debra Constantino's roommate, James Anderson, was found dead in his Reno home, Sparks police Lt. Rocky Triplett said.Mark and Debra Constantino starred in Travel Channel's Ghost AdventuresThe pair were both found dead in their daughter's Reno apartmentPolice say Mark Constantino fired at officers when they attempted to approach building, leading to a two-hour standoffA police source said he killed his wife then shot himselfMr Constantino is suspected of first shooting dead James Anderson, his wife's housemate, in the apartment the two sharedMrs Constantino was declared missing but tracked to daughter's home 
 Question:That's when they determined _ was missing and that she and her husband had a history of domestic violence and were in the process of getting divorced.

Debra