This evening Feather delivered six kits, but she did not prepare a proper nest for them. I had twice given her a nest box full of shavings, one she dumped out and pooped in, the second she peed in. Despite moving the nest box to try to prevent her thinking it's a potty spot, twice she soiled it, so I had pulled all the bedding out of it, thinking I could add more shavings once she'd made a nice fur nest. She didn't get that memo. When we arrived home tonight, six kits were scattered throughout the nest box, with a few tufts of hair. All the kits were cold and still. I handed the nest box to #3 and told her to bring them in the house. They all looked dead, but maybe if they warmed up they'd come back.
Of the six kits, two did eventually start to move. One took a few gasping breaths, but never recovered and after about ten minutes passed away in #3's hands as she tried to warm it up. The other one seems to have pulled through for now. It's warm and breathing, which I will count as a success.
As with Boon, a single kit will not survive the cold nights without litter mates to snuggle with and share body heat. So tonight, the little survivor is bunking with Boon in the kitchen.
I'm not sure if we will split them up and put them into separate nest boxes and nurse them on their moms, or if they will stay together and see if either momma will nurse them together. My concern would be that Boon, being much larger, will get all the milk, and the little one will starve. It might be best to separate them for feeding time, but for right now, they seem to be enjoying having a warm companion to snuggle with.