california can you change the fathers name on a birth certficate? when my son was born his father was not present. my friend said it was okay to put his name down not wanting to leave it blank. my sons father came into the picture soon after. about 5 years ago i went to a para leagal and at the time thought this was being done. my sons name was the only thing that changed. he now has his fathers name and see's him every other weekend. his father pays support. i need to fix this problem. can i? and how?