8 months preg and problems with my cat?

we have 3 cats and a 5 week old boy..we never lock them out of our room..except at night when we close the door to sleep..which we usually did before, even if i wake up to feed sean early in the morning then go back to bed for an hour or so..i leave the door open, the cat won't hurt the baby, and you don't have to keep them separated, that i think could actually lead to jealousy from the cat..just try to be as normal as possible and the cat will be fine..mine are totally indifferent to the baby..they'll sniff him, but they don't care as long as they still get attention and food, they'll lie right beside us, even when he cries, they're fine