Step-parent adoptions involve numerous complex legal issues. I strongly suggest that you obtain an experienced family law attorney to assist you with your case. That being said, before a step-parent adoption can go through, the biological father's legal relationship with the child must be terminated, either via relinquishment or an involuntary termination. You indicated that this adoption is "uncontested" which leads me to believe that the birth father is willing to relinquish his parental rights to the child. You do not need to be married to the prospective adoptive parent in order for the court to grant the petition for adoption. Good luck!
It sounds like you may have been led to believe that you can handle the step-parent adoption on your own. I would strongly advise against this as the Washington statues that control termination of the biological parent's rights and subsequent adoption of the child, lay out very specific requirements which you will need to comply with regardless of whether this is a contested or uncontested adoption. The court rules in your area may set out additional requirements. Generally, adoptions are not prohitively expensive and you should locate an attorney in your area who offers adoption services at a reasonable rare. Good luck!
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