Juan Mejia Alanis, 20, died at about 11:30 a.m. Monday at John Peter Smith Hospital in Fort Worth, police said.
Now that Collazo has said she left willingly, Sigala, 16, will face a charge of delinquent conduct/murder, instead of capital murder charges, police said.
Sigala was taken into custody at his parent's house Monday evening.
Collazos's sister, Erika Collazo, told the Star-Telegram that her sister and Sigala began dating in January, but had ended their relationship a few days ago.
Mirella Collazo was distraught over what happened and concerned about what would happen to Sigala, her sister told the paper.
"She was like, 'I'm never going to see Larry. What am I going to do without him?' " Erika Collazo said.
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