When Kaylyn Whitaker died in the Martinsville, Illinois home she shared with her fiancé, Connor Scott, he said he believed she committed suicide.

TELL DR. PHIL YOUR STORY: Terrible lies?

More than four years later, Connor Scott walked into an Indiana police station and confessed to shooting her. Scott, who initially pleaded not guilty to a charge of first-degree murder, later pleaded guilty in exchange for a reduced sentence. He is now serving 37 years behind bars.

Kaylyn’s mother, Leslie, says, while her daughter and Scott appeared to be very much in love, she believed there was also a dark side to their relationship. “She couldn’t do anything without him intervening with anything she did,” says Leslie, claiming that Scott was “very controlling” of Kaylyn.

WATCH: ‘Nobody Should Have To Die The Way My Daughter Did,’ Says Mother Of Murder Victim Kaylyn Whitaker

In the video above, Leslie describes the “red flags” she says she saw in Kaylyn’s relationship with Connor Scott, and why she says she felt her daughter was distancing herself from the family before she died.

This Dr. Phil exclusive airs Monday. Check here to find out where you can watch.

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