Cassandra Cales, sister of Stacy Peterson, speaks out in a new docuseries

By Steve Helling
September 03, 2015 06:35 PM
M. Spencer Green/AP

For eight long years, the family of 23-year-old Stacy Peterson has wondered where, exactly, she is.

That’s not to say they don’t have their suspicions.

After all, Stacy’s husband, former police officer Drew Peterson, has a track record of criminal behavior.

Drew Peterson was sentenced to 38 years in prison for the murder of his third wife, Kathleen Savio.

Savio’s 2004 drowning death was originally declared an accident, but authorities reopened the investigation in 2007, after Stacy Peterson vanished without a trace, and Drew was found guilty of the crime in 2012.

Stacy was Drew’s fourth wife. Stacy’s sister says that she knew something was wrong – and that she begged her sister to leave Drew Peterson just two days before her disappearance.”

Stacy looked at me and she goes, ‘So how do you feel about me getting a divorce from Drew?'” Stacy’s sister, Cassandra Cales, says on Saturday’s episode of Murder Made Me Famous on the Reelz Channel.

“Her face turned pale white,” recalls Cales. “She told me, ‘If anything ever happens to me, Drew did something.’ My heart stopped, and I said, ‘Let’s go. Let’s go right now.'”

But Stacy Peterson was afraid to leave. “She said, ‘I can’t,'” recalls Cales. “She said, ‘If I take the kids, he’s the breadwinner.’ That’s exactly what she said, that he’s the breadwinner.”

Two days later, Stacy Peterson disappeared without a trace. She has never been found.

Murder Made Me Famous combines reenactments, exclusive interviews and never-before-seen photos and video to tell the story of infamous murderers. Each episode of the show features PEOPLE Senior Writer Steve Helling. The show airs Saturday night at 9 p.m. on the Reelz Channel.

Check out an exclusive preview below!

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