Does not having a birth certificate disallow someone from obtaining a social security card?

I believe you will. I am not sure what other verification you would have of a birth other than a birth certificate but I suppose you can present it to the social security administration and see what they say.

I recommend getting the birth certificate. You'll need it sooner than you think for all sorts of things and it's better to get this out of the way.

You should apply for a birth certificate, so that Social Security can issue a number for your son. Below is a link to information from Social Security about how to obtain a SS number for your child. From the online info, it appears that it is easier (and faster) to get a minor child's SS number through the agency that issues birth certificates.

I have to agree with Attorney Lewis. There will be other occasions when you will need a birth certificate so you may as well get one now. Most places asking for one, even want to see the birth certificate with a seal on it. Then they may make their own copy if it's needed for some purpose like school. When you get the birth certificate, make one or two copies and put them somewhere safe, so you will remember where you put it. It is also especially frustrating to produce a copy of a birth certificate, only to be told: "sorry, we need to see one with the seal on it." You should have a copy of your own birth certificate as well. When you get the Social Security Card, make sure you put it somewhere safe, too.

To add to the other responses, you should contact the County Clerk's Office in the county in which you were born in order to obtain a certified copy of your birth certificate.