Matthew Perry’s sister, Caitlin Morrison, trashed his assistant, Kenneth Iwamasa, as she suggested he serve hard time in prison for his role in the late actor’s death, TMZ has learned. 

Caitlin wrote a letter ahead of Kenneth’s sentencing, saying she doesn’t have “sympathy” for the assistant. 

In her message, Caitlin said, “No matter what happens in the case, my big brother … will be dead.” 

“I almost feel bad for them,” she said. “I’m an immoral way to make a living, if you ask me, but they are few of many and it’s hard luck to be the ones who end up with tarnished names and time to do.” 

“I can find sympathy for just about anyone, you see. I have no sympathy for Kenny Iwamasa,” she said.

Caitlin said she wasn’t there the night Matthew died on October 28, 2023. “I cannot read Kenny’s thoughts. I will never know if the lethal dose of ketamine was only lethal by accident.” 

“I would be foolish to say that I could never make a life-or-death kind of mistake,” Caitlin said. 

She added, “I hope I never do, of course. In the shock of such a thing, I can see how I might want to run away from what had happened.”

The letter continued, “What I would not do is hound the grieving family left behind. I would not weave a story to cover my tracks. I would not try to extort a payout from a mother whose first-born son’s life had been lost at my hands.”

Caitlin said she doesn’t know what Kenneth was doing, but hopes someday he understands the gravity of his actions. 

“If you ask me, he could use a good long time to think about it,” the note ended.