Sara Gilson‘s cause of death has been determined more than two months after she was allegedly killed by her estranged husband in an Oklahoma murder-suicide.

According to medical examiner documents obtained by PEOPLE… Gilson died from a gunshot wound to the head. Her manner of death was ruled a homicide.

Jeremiah “Shawn” Duffey‘s death was ruled a suicide, and toxicology testing was negative.

Owasso Police previously said Duffey shot Gilson before killing himself inside her home on July 23. A child inside the home called 911 and Gilson could seemingly be heard “screaming and crying” in the background before a loud bang.

Duffey was under investigation for alleged lewd molestation of a minor at the time of the shooting. Weeks earlier, Gilson had filed for an emergency protective order against him after authorities said he had inappropriately touched a 15-year-old girl on a youth basketball team he coached.

A separate protective order was filed on behalf of the teenager. Police said the alleged conduct had reportedly occurred over an extended period and across multiple states. The case had been referred to the U.S. Attorney’s Office for review before Gilson’s death … the investigation has since been closed.