"We are sad to inform you that our incredible, fierce and loving mother has passed away, " her children wrote.

Alley won an Emmy award for her role as a pub manager on the popular TV series.

The native of Wichita, Kansas, has also appeared in the films Star Trek II: The Wrath of Khan, Drop Dead Gorgeous, and the Look Who's Talking series.

The family statement did not specify what cancer she had, but said it was "only recently discovered".

"She was surrounded by her closest family and fought with great strength, leaving us with a certainty of her never-ending joy of living and whatever adventures lie ahead," it continued.

"As iconic as she was on screen, she was an even more amazing mother and grandmother."

They also praised her "zest and passion for life, her children, grandchildren and her many animals, not to mention her eternal joy of creating".

John Travolta, who co-starred with her in the Look Who's Talking series, took to Instagram to pay his respects.

"Kirstie was one of the most special relationships I've ever had. I love you Kirstie," he wrote alongside a photo of her.

"I know we will see each other again."

On Cheers, the beloved NBC sitcom about a bar in Boston, she played the character Rebecca Howe opposite actor Ted Danson.

She appeared in 147 episodes after joining the show at the height of its popularity and continued to appear until its end in 1993.

In 1993, she won a second Emmy for best lead actress, this time for a CBS TV movie called David's Mother.

BBC