JonBenet Ramsey's Brother Speaks Out on Sister's Unsolved Murder Nearly 20 Years After Her Death

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It's been nearly two decades since JonBenet Ramsey was found beaten and strangled in the basement of her family's Colorado home.

In a sneak peek look from a sit-down interview with Dr. Phil airing next month, the 6-year-old beauty pageant star's brother, Burke, finally opens up about the mysterious murder, revealing shocking, never-before-heard details about the famous Dec. 1996 case.

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"I remember my mom searching my room that night saying, 'Where's my baby? Where's my baby?'" Burke reveals in his first-ever media interview. "I know people think I did it; that my parents did it. I know that we were suspects."

"I want to honor her memory by doing this interview," he adds. "I don't want anyone to forget."

Burke was only 9-years-old when his sister died, but he says he still remembers specific moments from the unsolved case and her funeral clearly.

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"I remember the viewing," Burke, now 29, shares. "The casket was small. Her eyes were closed."

More than 140 suspects and 1,400 pieces of evidence have been reviewed in JonBenet's murder, one of America's most talked-about cold cases. Burke and JonBenet's parents, John and Patsy (who died in 2006 after a battle with ovarian cancer), were the primary suspects for more than a decade until police cleared them of any wrongdoing in 2008. The two made the initial call to police, saying they found a note demanding ransom for their daughter of $118,000. John later found his daughter's body hours after police completed a search of the home.

The three-part season 15 premiere of Dr. Phil -- which will also air never-before-seen interrogation interviews conducted with Burke when he was 9 and 12 years old -- kicks off Monday, Sept. 12 and continues Tuesday, Sept. 13 and Monday, Sept. 19.

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CBS is also revisiting the crime that transfixed the nation in a docu-series titled The Case of: JonBenet Ramsey. The six-hour limited series features a team of experts (including a few of the case's original investigators), who will re-examine the evidence 20 years later.

Watch the video below to see a sneak peek look at the series ahead of its premiere on Sunday, Sept. 18 at 8:30 p.m. ET.