I recommend trying to feed her "Royal Canin Feline Health Nutrition Mother & Babycat Dry Cat Food" if you're letting her have the kittens. But she should be taken in to be spayed ASAP. There are youtube videos on how to trap cats safely, and if not, reach out to your local trap, neuter, and...
Her nipples won't start to pink up until week 2-3. I would definitely recommend you spay and neuter both cats ASAP! There is a huge overpopulation of cats and the more cats born means more cats are put down in shelters. If you want kittens, you can adopt at your local animal shelter.
It's been 6 years since this post, but anyone reading it now, it is a cause of concern if there's more than about 3 hours between kittens. Don't hesitate to call your vet!
