Kim Kardashian and her half-sister Kendall Jenner have both been criticized for their weight - but for opposite reasons.

Kardashian, who is several months pregnant with her first child, recently slammed claims she weighed over 200 pounds, as a tabloid recently suggested. The reality star, 32, has also faced a lot of criticism over her maternity wear, which often shows off her curves and is either too tight or too loose.

It seems that no matter what Kardashian wears, someone doesn't like it and blogs about it.

Meanwhile, Jenner, 17, says she is often targeted for being too thin. She told Harper's Bazaar Arabia:  "I am constantly criticized for being too skinny. I'm trying to gain weight but my body won't let it happen. What people don't understand is that calling someone too skinny is the same as calling someone too fat, it's not a nice feeling."

The sisters both star in "Keeping Up With The Kardashians," and Jenner has successfully launched a modeling career, appearing in several magazines and strutting down the catwalk at New York Fashion Week.

Check out two slideshows below of the sisters...