Kim Kardashian's kitten Mercy has died and the 'Keeping Up With The Kardashians' star is very sad over the loss. The kitten was featured on social media when Kim first received her as a gift. Kim received the white Persian cat from her boyfriend Kanye West in September but after discovering she was allergic, she gave him to her sister Khloe's assistant Sydney Hitchcock, who had recently lost her own cat. However, after Mercy became ill in November, she was rushed to a vet where she was diagnosed with a fatal cancer like virus which attacked her stomach and both Kim and Sydney are devastated. A source told E! News: ''Kim is really upset. She was upset about Mercy dying and upset that she was trying to do something nice for Sydney and then she fell into a situation where [Sydney] had to grieve another kitty.