A California prison panel denied parole to slay ring kingpin CHARLES MANSON in his 12th bid for freedom.

The Helter Skelter ringleader, 77, didn’t even appear at a hearing in Corcoran State Prison to get the thumbs down but one of his slay gang vic’s sister did.

Sharon Tate’s sister, Debra, has spent the past four decades traveling to prisons scattered across California whenever Manson is up for parole to remind one and all of the depth of his cruel evil.

"I've tried to take this thing that I do, that has become my lot in life, and make it have purpose," Tate, 59, said.

"I've been doing it for Sharon and the other victims of him for the last 40 years."

Debra’s older sister who was married to director Roman Polanski was eight-and-a-half months pregnant when she was stabbed 16 times in the belly by Manson’s thrill kill cultists.

Manson was originally sentenced to death for masterminding the murders committed by his followers but his sentence was modified to life in prison with the possibility of parole in 1977.

With this rejection Manson won’t be eligible for parole for another 15 years, when he’ll be 92.

"At his age, I think he doesn't care," said Deputy District Attorney Patrick Sequeira, who argued against Manson's release.

"He would be lost if he got out. He's completely institutionalized."

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