It is a myth that all kittens are born with worms, it is entirely possible they do have worms but not a given. You won't see them until they reach a certain stage and then depending on what type, you will see them. The best thing to do is run a fecal from mom into the vet for testing, if she has them so do the kittens.
The only way to tell for 100% absolutely certain whether or not your kittens have worms is by having the vet perform a fecal exam - and even then it isn't 100% accurate.
That now being said, no, not all not all kittens acquire worms from their mother as a general course. My own kittens did not and they were each tested many times over the course of their stay here with me.
Not necessarily, however, to be on the safe side, since worms can lead to other very serious illnessess if left untreated, get the cats dewormed at the appropriate age. Have your vet deworm them with Strongid when he deems them ready. Hope that helps. (FYI most of the cheap stuff you buy at grocery stores does not worm them properly and can potentionally hurt them...it's much cheaper to have it done by a vetrinarian, it can save you heafty medical bills incase you dose them incorrectly. So i advise your vet deworm them with Strongid just to be safe. Good luck!!