Kelsey Grammer Hopes to ‘Breathe Life’ Into His Late Sister Karen with His Emotional New Book (Exclusive)

• In his new book Karen: A Brother Remembers, Kelsey Grammer opens up about the horrific murder of his late sister in 1975
• Grammer’s wife Kayte Walsh was the first person he told about the book
• “For a long time, the grief was so dominant that I couldn’t access happiness,” Grammer tells PEOPLE exclusively. “The book helped me get to a new place with that. Karen gave me a great gift.”

Kelsey Grammer is honoring his late sister Karen in a big way.

In his new book Karen: A Brother Remembers, out May 6, the Frasier star, 70, delves into the horrific details of his 18-year-old sister’s 1975 murder in Colorado Springs, Colo., as well as the deep and lasting toll it took on his life, which has been touched by multiple tragedies.

“For a long time, the grief was so dominant that I couldn’t access happiness,” Grammer tells PEOPLE exclusively. “The book helped me get to a new place with that. Karen gave me a great gift.”

Grammer also doesn’t want his sister to be remembered solely for the worst thing that happened to her. He paints a picture of Karen as a free-spirited and loving woman who made the most of every moment, whose life was so much more than the way it ended.

“I wanted to breathe life into her and welcome her into the world,” he says. “We were Kelsey and Karen, brother and sister. It was nice to see Karen and nice to see younger Kelsey, too. It became a doorway into this relationship that’s still going on.”

As children, Grammer and his sister weathered much together, beginning with their parents’ divorce in 1957 when Kelsey was a toddler and Karen only a few months old. After the split, the siblings moved with their mom Sally, a dancer, from St. Thomas in the U.S. Virgin Islands to her parents’ home in New Jersey, while their dad Allen, a music shop owner and publisher, stayed behind.

Grammer and his sister didn’t see their dad again until 1967. That same year, the siblings lost their beloved maternal grandfather, Gordon, to cancer.

A year later, Allen was shot and killed at his home in St. Thomas by a taxi driver amid a wave of racial violence following the assassination of Martin Luther King Jr. The killer was found not guilty by reason of insanity, and it’s still not known exactly why Allen was targeted.

“He was 38 years old when he died, which didn’t really hit me until I turned 38 and realized how young he had been,” Grammer says. “That’s just barely getting started.”

Karen moved to Colorado Springs after a semester at college in Georgia to be with her boyfriend. Grammer last spoke to his sister on June 30, 1975, and she told him she planned to come home to Florida after the Fourth of July.

When he didn’t hear from her again, Grammer called the local police. He later found out that just hours after he and Karen had chatted, she went to the Red Lobster where she worked at around 11 p.m. to wait for a friend to finish their shift. Freddie Glenn and two others had planned to rob the Red Lobster, but when they pulled up behind the restaurant, they spotted Karen.

Karen was taken to Glenn’s car and was left with him as the other men entered the restaurant and ultimately decided against the robbery. When they returned, they found Karen tied up next to Glenn. They drove her to one of the men’s apartments, where they took turns raping her. The men drove Karen to an alley, where Glenn stabbed her 42 times.

Glenn was convicted of Karen’s murder and several other murders in the area. He is currently serving a life sentence in prison and has been denied parole four times. His next hearing is in 2027.

“Almost 20 years ago he could start asking for parole,” Grammer says. “His protestations these days are like, ‘Well, I don’t remember raping her.’ Bulls—.”

While Grammer has said in the past that he forgives Glenn for his actions, he still holds him accountable.

“It’s more of a rhetorical forgiveness: you don’t want to eat yourself to pieces because you can’t forgive somebody,” he says. “But it’s hard to forgive a person who consciously decided they wanted to murder somebody you love. This wasn’t just some temperance issue with him. It was deliberate. I can give you forgiveness, but you’re not going to get out of paying for it.”

By sharing Karen’s story with the world,­ Grammer hopes to help other families who are coping with violence and loss. The book fittingly ends with a pilgrimage to Colorado Springs to retrace Karen’s last steps.

“I had to complete my farewell to her. I had to be there and hold her in the end,” he says. “It became important to get the closure. I hate clichéd words like closure, but I got the opportunity to say all the things I never said.”

When Grammer finished writing, his wife of 14 years Kayte Walsh was the first person he told.

“She said, ‘Well, I’ve missed you,’” he recalls, tears welling up in his eyes. “I had to go away for a while — there were hours on end that I would just be staring off. But she was patient and loving through it. I had definitely lost a lot of the joy, and this brought it back for me.”

Karen: A Brother Remembers comes out May 6 and is available for preorder now, wherever books are sold.