If this is his bio father nothing hes his son in the eyes of the court
How Much Does It Cost To Change My Sons Last Name To His Fathers Last Name?
You can get the legal name change forms you need to change your son's last name to his father's last name at [ LegalFormsBank.biz ]. Your county's clerk office will charge you a fee and I can't tell you how much it will be unless I know which state you live in.