Amen to that!! @LilDude - you have saved those kitties from a terrible fate. The small county rural shelters do not have same resources that more urban areas do so cats tend to be low priority. Adding to that, shelters that are old-school are not designed for the comfort of the animals and the din from the dog rooms tends to be terrifying to other dogs not to mention what it does to cats. I have visited shelters all over the country and met many shelter attendants - it is common for pregnant cats to become so stressed that they deliver too early and the babies don't make itI am here if you need me. Moving cats here right now because of AC failure but you know how to get me. I know you are doing fine though. You have great instincts and you are getting great support and advice here.
But now these kitties are with you and we can all focus on the bright future that you are making possible!! Their past in the shelter is behind them and they are getting to be kittens in a safe place; free to play and learn and grow. They are so adorable!
And in case you did not know it, kittens (and puppies) often have different fathers. The moms don't ovulate until AFTER mating. And since mating as well as ovulation can take place at different times, the babies can be born at different stages of development. Each unborn kitten has its own placenta and sack; a cat can have most of her litter on one day and then up to 2 weeks later have another kitten! I used to see it alot when I was a kid, especially among the dogs - the hunters would keep a purebred bitch and breed her but since dogs were mostly outside in those days, other males would dig under the fence and those puppies were called "throwbacks" and often destroyed.