Our Kitten Tragedy

Yesterday was a very sad day for us as we lost all of our sweet little kitties. The mother had started acting weird Thursday morning, not wanting to be in with them or nurse them. I let her outside in the morning and she headed off into the woods and didn't return until last night. We have a feeling that something was wrong with them or that they weren't nursing correctly and just slowly became weaker and weaker. By the time I realized that something might be wrong, it was too late. I feel just terrible; we were so excited to have the joy of kittens in our home and now they're gone. The kids are taking it surprisingly well and only shed a few tears; they weren't that attached yet because I had tried to keep them away from the kittens so as to not freak out the mother. The mother cat is definitely getting fixed soon because I don't want to go through something like this again.