How can I amend a birth certificate (in CA) and change my child's last name from my maiden name to my husbands name? The social security card and medical records already have my husbands last name just not the birth certificate. I would like the birth certificate to be accurate to everything else.

Well first how did you get the social security card with one name? Since they require documentation?? But is husband the actual father, if he is the bio father, you may be able to have him added to the birth certificate, but it is very likely if you have waited a while You will have to go to court and have the name changed, since the child's bio father is wanting to have it changed to his name and you agree, it shoul be easy.

Now if your husband is not the bio father, you will have to get the bio father to approve. Also if you registered some other name than the real name for a social security card that can be a problem also.