Sounds normal to me, you just need to watch for other signs such as vomiting, lethargy. They will need to see the vet in another week or so for their first round of wormer and that may be what is going on with the diarrhea. You can start litter training them now, if you haven’t started already.Get boxes that are low for them to get in and out of easily, with plain, unscented, non clumping litter to start with. Kittens have a tendency to eat litter at first sometimes so it’s best to use the non clumping in the beginning.
Be glad your baby is pooping after every meal, it’s nice to be predictable. You can pop her into the litter box and she can do her business. Cats have a natural tendency to want to bury their poo, so she should take to it quite easily. The other one may see her and follow suit. Diet can cause diarrhea, along with other things. Just watch them and if they should become inactive and sickly, they could have other parasites that a vet can treat but may need a stool sample to test for.
Congratulations on becoming a cat mom!
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