Kelsey Grammer opened up recently about the devastating murder of his sister, BBC Radio reports.

Grammer, best known for starring in television shows such as Frasier and Cheers, was interviewed by BBC Radio 4’s “Desert Island Discs” program.

The 62-year-old said he has forgiven the man who brutally took the life of his sister Karen Grammer in 1975.

“I have learned to forgive,” Grammer said. “I have even told the guy I forgive him, although I don’t advocate his freedom. I don’t think that is reasonable.”

Grammer has opposed efforts by the killer, Freddie Glenn, to get parole.

“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,” Grammer told the BBC.

At the time of his sister’s murder, Grammer was 20. He said the experience nearly consumed him and shattered his belief in God, although he has since renewed his faith.

A jury convicted Glenn in 1976 of killing 18-year-old Karen Grammer and also murdering two other victims.

Glenn and an accomplice, Michael Corbett, kidnapped Karen Grammer outside a Red Lobster as she was waiting for her boyfriend to finish his shift.

The thieves had made a failed effort at robbing the restaurant and believed that Karen Grammer could make out their identities.

The men raped her repeatedly for more than four hours, KKTV reports, and then told her she would be released.

Instead, Glenn, who was 18 then, slit the woman’s throat and left her to die. He reportedly had taken LSD at the time.

Karen Grammer was able to reach a nearby home for help, but no one was there at the time and she died on the house’s back porch.

A week later, Kelsey Grammer identified her body.

Glenn was sentenced to death, but the Supreme Court overturned that sentence and allowed him to seek parole.

Kelsey Grammer has continually advocated for his sister since. When Glenn’s parole was up for consideration in 2009, Kelsey wrote to officials.

“She was my best friend and the best person I knew,” he wrote. “She had so much to live for. I loved my sister, Karen. I miss her. I miss her in my bones.

“I was her big brother. I was supposed to protect her — I could not. I have never gotten over it … It very nearly destroyed me.”

In addition to killing Karen Grammer, Glenn also murdered Daniel Van Lone, 28, and 19-year-old soldier Winfred Proffitt.

Glenn remains behind bars at a Colorado prison.

The killing of Kelsey Grammer’s sister isn’t the only anguish he has experienced in life. His father also was murdered and two half-brothers died in a scuba-diving incident.

[Feature image: Associated Press]