Dad will need to be legally established and legally relinquish his rights. Use an adoption attorney, make sure you don't try to take any shortcuts.
http://www.adoptionsolutions.com/general/state laws/ms_law.htm
Mississippi Adoption Statute Summary
Mississippi Code Annotated Sections 93-17-1 to 93-17-223 (1998)
Who Can Adopt?
Any adult who has resided in the State for at least 90 days prior to the filing of the petition may adopt. A husband and wife must jointly adopt.
Who Can Be Adopted?
Any person can be adopted.
Consent to Adoption
Written consent is required of the following people:
1. both natural parents, or parent, if only one parent;
2. if the parents are dead, then any two adult relatives within the third degree of the child;
3. the guardian ad litem of an abandoned child;
4. any person who has physical custody, or to whom custody has been awarded through the court;
5. the agent of the county department of public welfare who has placed the child; and
6. the adoptee who is over 14 years of age.
If the adoptee is born out of wedlock, the father shall not be deemed to be a parent and no reference shall be made to him.
Parental consent is not required if
1. the parent has abandoned or deserted the child;
2. the parent is mentally, morally, or otherwise unfit to raise and train the child;
3. the parent's parental rights have been terminated; or
4. the child has been removed from a parent's home and cannot be returned within a reasonable length of time because it would be damaging to the child, or the parent is unable or unwilling to take care of the child.
Any required consent shall not occur until seventy-two hours after the adoptee is born.
Confidentiality
All adoption proceedings shall be confidential and held in a closed court. All adoption records shall be confidential and shall not be public record and shall be withheld from public inspection, except upon a court order.
No reference shall be made to the marital status of the natural parents. The papers that are present during the adoption hearing shall not contain the names of the biological parents. The clerk of the court shall keep a separate confidential index showing the names of the biological parents.
The Bureau of Vital Records of the Mississippi State Board of Health shall maintain a centralized adoption records file. A revocable affidavit may be filed by any birth parent either authorizing or prohibiting the release of identifying information. Any adoptee over 21 years of age may request identifying information regarding his/her birth parents. Consent to release of this information must be obtained from both parents, otherwise the parent granting the release may not divulge the identity of the parent refusing such release of information. Any nonidentifying information may be released to an adoptee 18 years of age or older, an adoptive parent, or the adoptee's offspring or blood sibling 18 years or older.
The adoptive parents or an adoptee at least 18 years of age (or a sibling) may obtain any nonidentifying information through a written request. Any information obtained by the Bureau concerning a genetically transferable disease or illness must automatically be given to the adoptive parents or the adoptee, if 21 years of age or over.
Permissible Fees
A reasonable fee, as determined and approved by the court, may be charged for the preadoption investigation. All other costs of the proceeding shall be charged in the manner that the court may direct.
Place of Adoption Hearing
The adoption hearing shall take place in the county where the adoptive parents reside, where the adoptee resides, where the adoptee was found when abandoned or deserted, or where the home that the adoptee is temporarily placed in is located.
Authority To Place Child
Any charitable or religious corporation, organization, or superintendent or head of such charitable or religious corporation, organization organized under thelaws of the State, or any public authority, that is authorized to provide care or place children for adoption, and any association or institution that places children for adoption can place a child.
Relative Adoption
The requirement that the adoptive parent has been a resident of the State for at least 90 days shall not apply in the case of relative adoptions.