We have a 12 week old kitten who didn't pee for almost 24 hours. She then decided to pee in the bin with the news papers and there was a big amount. She had a sister that passed away this week from an intestinal disease and I am wondering if she is missing her. I have put her litter box downstairs and am wondering if she needs one now upstairs. I guess I am a little nervous because the other kitten died. Any help is appreciated.