Sounds like your son ment well, i'm sure he is very good with animals...you raised him well. if you need help as far as having the kittens vaccinated and altared please let me know. i'm not sure where u live, but if you are in the USA there are tons of shelters/ rescue groups and vet clinics that provide low cost spay/neuters as well as shots. In the mean time, i would definitely keep her and the other kittens away from any male cats. best of luck!!