The incident happened in San Marcos, but Eyewitness News has learned two of those involved have ties to the Houston area.
Hailey Nicholls, 22, lived in Kingwood. Her ex-boyfriend, who police say killed her, lived in northwest Houston.
We talked to Nicholls' mother, father and older sister. They said Nicholls was senselessly taken from them and don't understand why. Investigators say this may have been a case of a love affair gone terribly wrong.
"I heard the girl ask, 'Why are you here?'" a neighbor said.
Their love affair turned deadly early Thursday morning when police say 23-year-old Daniel Brewster Stillwell confronted Nicholls and her 27-year-old boyfriend, Jesse Robledo, in a San Marcos apartment.
According to police, Nicholls was shot in head on the floor. Robledo was also shot in the head; his body was found on the bed.
"The breakup between the ex-boyfriend and girlfriend -- between Stillwell and Nicholls -- was, to my understanding, very recent. It's about the best I can tell you for sure. But yeah, it's going to be a recent breakup issue," San Marcos Police Chief Howard Williams said.
Robledo was from San Antonio. His father calmly described how he found out about the killings.
"The police, they just sat us down and said to us basically that my son was deceased," he told WOAI in San Antonio.
For hours, police looked for Stillwell. According to police, he called his roommate and said he hurt his girlfriend. Before police could catch him, he drove his car off cliff in an area of Comal County known as Devil's Backbone.
"I've been here 10 years now, this is first time we've had a double murder in that sort of tradition," Williams said.
Nicholls had a identical twin sister. Her mother told me her heart also goes out to the other two families who are grieving right now. She says right now, three families are at a loss.
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