Kelsey Grammer was 20 when his younger sister was murdered. He never wants the killer released.

Karen Grammer was just 18 years old when she was brutally raped and murdered in 1975.

Karen, the younger sister of Frasier’s Kelsey Grammer, was waiting for her boyfriend to finish work in the car park of a Red Lobster restaurant in Colorado Springs on the night of her murder.

She was suddenly snatched out of her car by two men – Freddie Glenn and Michael Corbett – as they fled the restaurant.

The criminals had just attempted to rob the Red Lobster and they feared Grammer could identify them.

But this fear was no excuse for what they did next.

Glenn and Corbett took Grammer back to an apartment and repeatedly raped her over a four hour period.

They then told the 18-year-old she would be let go and released her from a car in a nearby trailer park.

But her dash for freedom was cut short when Glenn, who was reportedly on LSD at the time, brutally wounded her.

The terrified teenager managed to make it to a nearby mobile home to find help, but no one was there.  She died on a stranger's back porch.

One week later her older brother Kelsey, then 20 years old, identified her body at the morgue.

Karen's killer had previously murdered motel cook Daniel Van Loene, 28, after he robbed him of 50 cents on June 19, 1975.

Seven days later he killed a 19-year-old army soldier named Winfred Proffitt over drugs. He was just 18 years old when he murdered Karen.

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Glenn was eventually convicted of Karen's murder and sentenced to death. The Supreme Court later overturned that sentence, instead allowing him to seek parole after 30 years.

Kelsey, however, has made it his life mission to never see the man who murdered his little sister set free.

Speaking to BBC Radio 4’s Desert Island Discs this week, Kelsey says he has forgiven his sister's killer but he never wants him to be released from jail.

"I have learnt to forgive. I have even told the guy I forgive him, although I don’t advocate his freedom. I don’t think that is reasonable," the now 62-year-old said.

"In a letter to the parole board, I said the punishment shouldn’t be worse for the family than it is for the guy that killed the person and that’s what this feels like sometimes."

Kelsey said at the time the murder almost pushed him over the edge and he lost his belief in God for quite a few years.

The Cheers star has since restored his faith and embraced the concept of forgiveness, but he'll never forget the sheer brutality his sister suffered at the hands of her killer that night.

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