Legal Question in Family Law in Washington

Re: Step parent adoption

The answer is yes, but what that means is affected by information that is not provided in your question. That relates to the marital status of the father and what documents may have been signed by him. If the father was married to the mother at the time of birth, then the husband is presumed to be the father, and paternity is established or if hew was not married but the father signed the affidavit of paternity or signed on the birth certificate.