Sorry for the lack of details - I was so shocked we got them.

We have mom and all three kittens. Kittens are still nursing, although they're pretty big, especially compared to mom. She's actually pretty friendly, whenever I'm in here we have a game of see how often she can headbuttt my hands, regardless of what I'm doing. We had a look and didn't see any fleas on mom or the kittens, but I dosed Mom with Revolution anyway since it said it was safe for lactating moms. We're hoping to get everyone to the vet either tomorrow or thursday. The office can be closed off. It's actually where Cotton lived when we were first introducing him to Freya.
Right now the kittens are nested in a giant dog crate we borrowed from the neighbours and covered in a blanket. They also have a cardboard box in there and an old bedsheet. It looks like we have one grey tabby with white, one brown tabby with white and one solid grey with white and man do they ever have some solid lungs on them. Mom is a black and white DMH with the tiniest, squeakiest voice
Mom is currently alternating between lounging on the floor while I type and hanging out in the office window. She's eating and drinking like a champ and has very good litterbox habits. When I head to work I'll close her back in the crate just for safety. Freya hasn't figured out how to open this door yet, but better safe than sorry.
What breaks my heart is that she's so young...We've been calling her Sybil since it seems wrong that she's a mom at her age.