I hope I got their sex determinations right. Sometimes its easier to tell than others when they are that small. Dr. Fox of Riverbridge Animal Hospital will confirm that. Momma will get her surgery another day. Trying to do them all the same day and capturing the mom would have made the experience too stressful for all.
Btw, are you looking for a vet? Support vets who support rescue organizations!! The more involved they are with a rescue, the more experience they may have dealing with all kinds of crazy pet ailments, and it shows they care more about animals than just making money.