gurl2005bby, as I said before, there are a hundred things that could cause the biting behavior and/or neurological signs in a kitten this age or any other pet, anything from malnourishment, to a developmental problem (that may be able to be resolved with proper veterinary care), to a virus, to bacterial infection, etc etc etc. The momma cat trying to reject the kitten may be indicative he is ill in some way and truly should be examined by a vet. If rabies were suspect, the mamma cat and her other kittens would probably all have the same symptoms, which is unlikely and more likely the kitten has a health issue that should be addressed/treated by a competent, compassionate vet.
I would caution you about being complacent about bites/rabies. You of course always have the option of rabies prophylaxis, however, if you do not have health insurance (and they may not cover this, depending on the situation), this could be an expensive treatment, and could be painful if you are not used to the injections the treatment requires (it is a 28-day treatment with subsequent injections). You could on the other hand, get a titer done by your physician, but for people who know they've been bit and suspect that bite was from a rabies-positive animal, then there's no time for a titer, prophylaxis/treatment is the only preventative/curative treatment.
If you are going to be working with ferals and strays, I strongly advise you check with your physician and at least get a tetanus booster, every 7-10 years. (this does not protect against rabies)
Rabies
Re: Rabies
..........Traci