Condolences to Mittens and you. Godspeed over Rainbow Bridge, little Cotton. You lived too short, but the love that bestowed upon you will last forever. How is Mittens coping with her loss; one of the saddest sounds in the world is a mama-kitty's meowrling for her missing baby I hope that she recovers soon, and that you both able to completely enjoy the rest of the litter's kittenhood.
I'm pretty sure Mittens rejected this kitten and she isn't acting like she even knows the little one is gone.
When I found her, her legs looked really funny, like bent back like they couldn't go forwards. I think perhaps there was something wrong with her and Mittens just let her go and let nature take it's coarse.
It was sad, esp. since this is the 3rd kitten that has passed for me personally, so it was hard to go through that again. Atleast though, that this kittens suffering did not last long.