"It is with deep sadness that I have to tell you all that my kitten, Mercy, has passed away," Kardashian wrote. "My heart is completely broken."
After receiving the fluffy white furball from West, Kardashian discovered she was allergic to it and was forced to give it to her sister Khloe's assistant, Sydney.
"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," she explained. "Mercy deserved a mom who could really give her the time and affection she deserved."
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But soon afterwards, the teacup Persian kitten became ill and a visit to the vet revealed that she had a rare form of stomach cancer, according to Kardashian. "Poor little Mercy died the very next day," Kardashian wrote. "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. Thanks to Sydney for making Mercy's short life one filled with love."