As soon as he learned that his mother was dead, an 18-year-old high school senior in Indiana said Sunday he was sure the woman's boyfriend pulled the trigger.

Police in Greensburg said 43-year-old Jason Eaton admitted he killed 44-year-old Wendy Sabatini on Oct. 25 after she refused to marry him. Eaton said he approached her in their bedroom with an engagement ring, but before he could ask, she stopped him and said no, according to officers.

“I already knew that she was gonna say no,” Sabatini's son, Lake, told Fox 59. “She just didn’t want to get married again. She was married before. She just didn’t want to go do that again.”

Eaton then pulled out a gun from a nightstand and shot his girlfriend in the head, killing her, according to investigators. He eventually turned himself in to police.

Lake Sabatini said he was on the couch in his family's living room when police arrived and told him about the shooting. “One of the officers said, ‘I know where your mom’s boyfriend is at,’ and I said, ‘He’s with you, isn’t he?’ and I instantly knew that he killed my mom.”

He said the family knew Eaton had a “rough past,” but treated them well. The suspect faces a murder charge.

Greensburg is nearly 50 miles southeast of Indianapolis.

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