My question involves a child name change laws in the State of Illinois I been having several problems in obtaining my child's passport due to her having a different last name. I will like to have her last name changed? Her left to mexico when she was 3 months old and never came back. I don't know of his were about she is now 5 years old and am limited to plan trips do to the fact she doesn't have my last name. What can I do to have it changed?