The beautiful white Persian kitten that boyfriend Kanye West gave to Kim Kardashian has died.

The reality star wrote on her blog on Friday, "It is with deep sadness that I have to tell you all that my kitten, Mercy, has passed away. My heart is completely broken."

The kitten died from a cancer-like virus associated with breeding. Due to allergies, Kim had to give the cat up to her sister Khloe's assistant Sydney, who recently lost a cat.

She explained, "I had fallen SO in love with Mercy that I wanted to try everything I could to keep her, but I didn’t think it was safe to resort to injections, and it wasn’t fair on Mercy, because I couldn’t play with her or give her as much attention as I wanted to. Mercy deserved a mom who could really give her the time and affection she deserved."

Kardashian added, "It broke not only my heart that little Mercy died at only four months old, but Sydney’s too. Mercy was a gentle and loving kitten and we are all going to miss her so much."