When the little Digress was born five years ago, we had two cats.. they were old.. one was 14 and one was 12 and they had gone from being mine, to having a husband and moving across the country... blah, blah, blah....there were never any problems and the older one was calico and as could have been the temperamental poster child for calicos. There was never a crib issue. They weren't allowed in it and didn't go. They were a little skittish at first, but that went away. We have tons of pictures of the younger cat sitting on our lap with the baby, usually on the baby's feet. The older one refused to cede her territory (me) to the baby, so she got grabbed and pulled, but never bit at the child. The funniest thing she did one day was smack the kid on the head about six times. Since she had no claws, I didn't worry about it.
I never once worried about one of my cats smothering my child or, especially, stealing their breath. That, I believe, is horse****.
The first day or so will be very weird, especially because the baby will smell different. But, just call me the cat whisperer, I think your progeny, once you get past the new baby smell, carries your odor and the cats will accept it into the herd.
By the way, those cats have since passed (cancer and kidney ailment).. we have three others. Kid gets way more scratched now because, she holds the cats and lays on the cats and ..you get the picture.