To accomplish an adoption, the parent who has custody of the child must file suit and give notice to the other parent of the child. It is possible that the father would be agreeable to the adoption of the child, and if he is, he can sign an affidavit to that effect. It depends on the judge concerning whether an attorney would be appointed to represent the child, an attorney ad litem, in a step-parent circumstance. If so, you can expect to pay that attorney as well, if that is required by the court.. Some judges don’t require an attorney ad litem in a step-parent scenario.