Kittening and other household cats

Question
Recently brought inside a stray/feral we've been working with for several months. Vet checked her out and other than a (now-defunct) hookworm, she's fine and healthy and adapting very well. Our other two older, spayed females are slowing warming up to the idea. Now the new one is pregnant and probably due while we're away. Do we need to isolate her in a closed bedroom with her birthing box or will it be safe for the other cats to have access to that room as well? A little bit of hiss/growl on their part (new cat wants to be friendly with them and doesn't care about the hiss/growl) but never any overt aggression.

Answer
Terry,

Yes, you need to isolate her in a closed bedroom with her birthing box.  I would wait until the kittens are weaned to let the two older spays have access.  Once kittens are born mamas can become incredibly protective, especially the first week after giving birth. If the mama becomes sufficiently agitated she could inadvertently harm her kittens!!!!!!

So, I would play it safe and not allow the other 2 cats access while she is giving birth or nursing.

BTW, spays have been known to try to steal kittens from the nursing mama which would be a major disaster for the kittens and nursing mama alike.

Bet regards... Norm.