A Texas teen allegedly murdered his 3-year-old stepson after the boy wouldn’t stop jumping on the bed, authorities said.

George Coty Wayman, 18, allegedly shot little Dominic Tra’Juan Castro in the head as the child bounced up and down on a bed at about 3 p.m. Tuesday, according to reports.

He told his stepson that he'd shoot if the boy didn’t stop jumping, authorities said.

Wayman then allegedly fired the gun, hitting Dominic in the back of the head.

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Emergency responders airlifted the boy to United Regional Health Care System in Wichita Falls, but he could not be saved. Dominic died there Wednesday morning, officials said.

Investigators were initially led to believe that Dominic had accidentally shot himself, but witnesses said Wayman shot his stepson, according to an arrest affidavit.

Several other people, including Dominic’s 30-year-old mother, were home at the time of the shooting, the affidavit said.

She and Wayman have been in a relationship since April 2015, she wrote on Facebook.

“He makes my kids happy,” she wrote of Wayman. “He makes me happy.”

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Loved ones shared their condolences with the woman, who had shared photos of herself with her son after he was killed.

“I’m sorry for your loss,” one person wrote. “Prayers for you all.”

“You poor sweetheart,” another person posted. “I’m so sorry. He’s so beautiful.”

Wayman was charged with capital murder and criminal trespassing, jail records show. His bail was set at $505,000. He is jailed in Clay County.

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