A 17-year-old boy in Texas is being charged as an adult after he allegedly murdered the stepfather of the girl he started stalking because she rebuffed his advances.

The Houston Police Department on Friday announced detectives arrested Cristian Gasca Martinez for murder in the death of 37-year-old Osvaldo Casas. Gasca Martinez allegedly shot Casas shortly before 12:30 a.m. Aug. 10 in the 600 block of Loper Street in southeast Houston. Cops responded to the scene and found Casas suffering from several gunshot wounds. Paramedics pronounced him dead on scene.

Police said at the time that Casas confronted a “suspicious” person on his street before the shooting. Further investigation determined that Gasca Martinez had been pursuing a romantic relationship with Casas’ 16-year-old stepdaughter, but the girl told him she was not interested, a complaint says. Gasca Martinez allegedly began stalking the girl. He kept calling the girl despite her asking him to refrain from doing so and she had to block his number, according to a courtroom report from local CBS affiliate KHOU.

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He also reportedly posted threats on social media that included posting photos of him holding a gun. Gasca Martinez then shot Casas “in retaliation for being rejected” by the girl, the complaint said.

In a GoFundMe page, the victim’s wife Judith Molina said her husband died “while bravely protecting our family.” Making matters even more tragic was the fact that Molina and Casas were expecting a baby boy. Casas’ family laid him to rest on Aug. 20. Three days later, Molina gave birth to a baby boy.

“Osvaldo was overjoyed at the thought of meeting his baby boy and becoming a father to a son,” she wrote.