Nearly five decades have passed since Karen Grammer, the younger sister of Kelsey Grammer, was savagely killed at just 18 years old, but the anguish over her tragic death is still raw for the 67-year-old actor.

“I’m actually writing a book about some of my past experiences, and one phrase comes to mind,” Grammer shares regarding the event in this week’s PEOPLE issue.

“It’s an ancient sorrow that’s perpetually new.’ It never leaves you.”

At the time of the incident, Grammer was a 20-year-old theater student at Juilliard in New York, while his sister Karen had just completed high school and relocated to Colorado Springs.

She worked at a Red Lobster there, and while waiting for her boyfriend to finish his shift, she was abducted by several men who had planned to rob the restaurant.

Instead, they kidnapped Karen, assaulted her multiple times, and eventually stabbed her to death.

Michael Corbett, one of the convicted murderers, died in prison in 2019.

Freddie Glenn, the other perpetrator, initially received a death sentence, but changes to Colorado’s death penalty laws made him eligible for parole after ten years.

Spencer Grammer, Kelsey’s daughter and his co-star in the upcoming Lifetime holiday film The 12 Days of Christmas Eve (releasing Nov. 26), says the possibility of her aunt’s killer being set free is harrowing for her father.

“Glenn becomes eligible for parole every few years, so every so often [my dad] has to speak against him,” Spencer, 39, clarifies.

“It’s incredibly hard for him to relive it time and time again. Plus, there’s very limited information available for victims’ families about potential releases,” she adds, explaining that this only exacerbates the pain for those families.

Spencer believes her father will never truly recover from Karen’s death.

“The loss of someone close to you, particularly in circumstances beyond your control, is incomprehensible,” the Rick and Morty actress elaborates.

“There’s no logic to someone stabbing or killing another person. It’s senseless and unacceptable.”

Karen’s murder was not the first, nor the last, devastating loss for the Frasier actor.

At 13, Kelsey’s father was fatally shot in St. Thomas by a deranged trespasser on his property.

Five years after Karen’s death, his two half-brothers, Billy and Stephen Grammer, were presumed dead in a likely shark attack while scuba diving off St. Thomas (Stephen’s body was discovered drowned on a nearby beach, while Billy’s was never found).

Kelsey admits that his past battles with substance abuse were likely a means of dealing with his pain.

“There were moments when I completely succumbed to despair,” he recalls.

Despite these tragedies, Kelsey has found happiness in family and maintained his faith in God.

Now married to Kayte Walsh and a father to three young children, he is thankful for the life he has and the love surrounding him.

As a Frasier reboot approaches, he also asserts that he has no plans to retire.

“I set aside time each morning for gratitude,” he remarks.

“There’s an excellent Doobie Brothers lyric by Michael McDonald that goes, ‘You’ll always have an opportunity to give up. So why do it now?'”