Please review the statute: 31-19-9 regards adoptions which is not the case here. So pursuant to 34-28-2-2 (b) consent from her father will be required. Consult an atty. particularly because you state you don't know where the father is. A diligent search will be required among possible other things.
Filing petition; procedure for change of name of minor
Sec. 2. (a) The petition described in section 1 of this chapter must:
(1) if applicable, include the information required by section 2.5 of this chapter;
(2) in the case of a petition filed by a person described in section 2.5 of this chapter, be subscribed and sworn to (or affirmed):
(A) under the penalties of perjury; and
(B) before a notary public or other person authorized to administer oaths; and
(3) be filed with the circuit court of the county in which the person resides.
(b) In the case of a parent or guardian who wishes to change the name of a minor child, the petition must be verified, and it must state in detail the reason the change is requested. In addition, except where a parent's consent is not required under IC 31-19-9, the written consent of a parent, or the written consent of the guardian if both parents are dead, must be filed with the petition.
(c) Before a minor child's name may be changed, the parents or guardian of the child must be served with a copy of the petition as required by the Indiana trial rules.
As added by P.L.1-1998, SEC.24. Amended by P.L.61-2010, SEC.1.
I agree with the other answer on this question as to if her stepfather wants to adopt her, then bio dad's consent may or may not be required based upon the statute. Another approach would be to file a formal name change without going through the adoption process. By filing a formal name change, the biological father would have to be served the pleadings (summons and notice of hearing). If he would consent, then that would help. However, if he has notice and you can show proof of notice, the court could default him if he fails to appear and the name change should then be ordered.
You could proceed with a stepparent adoption. It is likely based on the facts you have provided that consent of the biological father would not be required. Under the Indiana Code, if the child is adjudged to have been abandoned or deserted for at least six (6) months immediately preceding the date of the filing of the petition for adoption; the father fails without justifiable cause to communicate significantly with the child when able to do so; or the father knowingly failed to provide for the care and support of the child when able to do so as required by law or judicial decree (this meaning court-ordered child support), then consent is not required. Upon filing for adoption, it is true that you would have to make a diligent effort to attempt to locate the father for purposes of notice of the action. Since you do not know his location, you would likely do this through service by publication -- posting a notice in a newspaper.
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