The actress posted an IG video, showing her posing in a form-fitting black dress inside a trailer on the set of her new movie, "Stolen Girl." Kate was also seen dancing and goofing around with another woman.

The flick is based in the '90s, which is obvious from Kate's retro hair style and clothes -- and she even talks about it in her IG caption. But it was Kate's waif body that really caught everyone's attention.

In the comments section, Kate's fans criticized her thin figure with one writing: "Sorry to say this Kate, but you do look a bit thin. You always striked a great balance … But when your cheekbones start to show, the balance is lost."

Another said, "Kate! I think you've lost too much weight! You look amazing as usual but, put some weight on please!"

Several more people weighed in on the issue, causing Kate to angrily reply, "I have been really sad. I watched my second dad die. It made me sick. Sorry you find me less attractive. Couldn't give a f***."

Kate highlighted she had been there for her stepdad Ray Battersby until he died in January following a stroke. She mentioned her mother "also has stuff going on," while bringing up the death of her biological father Richard after he suffered a heart attack when she was only 5.

She also reminded her fans her "soulmate cat" passed away last year and that she spent six weeks in the hospital due to all the stress in her life, which ripped a hole "between my [esophagus] and stomach."