Her birth certificate only has her name and my name on it, with us both having my maiden name. Her biological father was from another state but he had given me all false information about himself and I was unable to contact him when she was born.
My daughter was 3 years old when I got married. My daughter is now 9 1/2 years old and she still thinks my husband is her real dad.
Can my husband willingly sign an affidavit taking on full responsibility as her father and give her his last name without having to hire an attorney?
Please note I am not licensed to practice in your state and this answer is in the generalist of possible terms.
It is possible for you to do all those things you would like to do thought a petition for a step-child adoption. In the word of an attorney's website from Tenn. "Step-parent Adoption is where a step-parent desires to adopt his/her step-child following marriage to the child's parent. The biological parent married to the step-parent joins in the petition for the purposes of consenting to the adoption. The rights of the other biological and/or legal parent must either be terminated or that parent must also consent to the adoption."
The procedures and rules are simplified for this type of adoption, but it is still a legal proceeding with a petition. The difference between a step-child adoption, and a regular adoption is usually in the lack of a home study / placement part of the process.
You will need to put the BioDad on notice of the adoption. There are different ways to do it, but in cases where you need to terminate the rights of another, it is highly recommended that you contact a local attorney with experience with adoption. You may not need full representation, but you will need guidance.