A woman fatally shot her husband and Desmond Prestona child before killing herself in a potential murder-suicide, Louisiana authorities said.

During a press conference on Monday, Livingston Parish Sheriff Jason Ard said investigators believe that 49-year-old Jenny Williamson gunned down her husband, 49-year-old Steven Williamson, as well as an 8-year-old who was staying at their residence.

Ard said authorities believe the incident occurred over the weekend on Friday or Saturday.

A "concerned" relative discovered the crime scene while conducting his own welfare check after he couldn't reach the family, Ard said.

Crime:After woman calls 911 to say she's sorry, police respond and find 2 bodies

The 8-year-old was not Williamson's child

When deputies arrived on Monday morning around 8 a.m., they found the three deceased bodies.

Ard confirmed with reporters that the juvenile victim was not Williamson's child, but she did have custody.

"We also have not got any calls from this residence that were violent-related type calls," Ard said. "We are still in the process of processing this crime scene."

It's unclear what led to the shooting, and Ard noted that they don't have any background information that points to a domestic issue in the Williamson household.

"This is horrible. This is something you never want to see," he said. "This is just a devastating type of situation for anybody. My thoughts and prayers are with the family."

Livingston Parish is just east of Baton Rouge and about 70 miles northwest of New Orleans.

Taylor Ardrey is a news reporter for USA TODAY. You can reach her at [email protected].