Almost immediately. My cat went into heat a few days after delivering.
You will need to confine her inside and make sure there is no way for her to get out. If she became pregnant that soon after, it is not healthy for her or the kittens.
Well, unfortunately, I think this may be the case. I am asking because the mother cat of the orange boy, Garfield, seems to be pregnant again, she is not my cat. I also took in her last two remaining kittens to hand raise, she refuses to care for them and they are very sickly.
So, now I have my original rescue, Garfield, and his two sisters... one will be staying with us, since my hubby fell in love.... her name is Nermal now..the other will get a forever home. I plan on fixing my two kittens as soon as possible so they will never be allowed to make more unwanted, uncared for babies.
Are you willing to have her spayed now? Its VERY hard to have another litter so soon - no time for mom to recoup. For her health, I'd have her spayed right now whether or not she is pregnant.
This 2nd batch of kittens could kill her or die because she's not physically ready (milk wise) to be nursing another batch.