Many were quick to express their sadness online, including John Travolta who worked with Kirstie on the Look Who's Talking film franchise.
"Kirstie was one of the most special relationships I’ve ever had. I love you Kirstie. I know we will see each other again," John wrote on Instagram.
Ever Carradine, who worked with Kirstie on the film, Veronica's Closet took to Twitter and wrote:
"I just head the news about #KirstieAlley. I’ve not spoke w/ her forever, but have her to thank for launching my career. She told me I was funny every single day on Veronica’s Closet, and I believed her. She threw the best parties and gave the parakeets as our wrap gift. Godspeed."
Kirstie began acting in the early 80s and made her film debut in Star Trek II: The Wrath of Khan. After appearing in a few other films, Kirstie's breakout role was Rebecca Howe in the sitcom, Cheers. Kirstie went on to earn an Emmy Award and a Golden Globe for the role.
This article originally appeared on our sister site, New Idea.