While technically you can adopt your girlfriend's daughter without being married, in order to do so your girlfriend would have to give up all parental rights to her daughter. As such, if you and your girlfriend ever split up, then you would receive full custody of the daughter and your girlfriend would be left out to dry.
Additionally, adoption can be somewhat costly...especially if the legal father wants to throw a wrench in the process. My suggestion to you would be to first marry your girlfriend, then focus on the adoption.
Finally, be honest with your daughter. Just because you don't have the same last name doesn't mean that you love her less, or that she isn't your "daughter." There are numerous books and reference material available to help parents explain situations in which you are in. It is better that she knows the truth now, rather than waiting.
Mr. Dial is licensed to practice law in IN with offices in Vanderburgh County. His phone number is 812-425-3592 or his email address is firstname.lastname@example.org.
Mr. Dial is ethically required to state that the response herein is not legal advice and does not create an attorney/ client relationship. Also, there are no recognized legal specialties under Indiana law. Any references to a trust, estate, guardianship, business or adoption lawyer refer only to the fact that Mr. Dial limits his practice to these areas of the law. These responses are only in the form of legal education and are intended to only provide general information about the matter within the question. Oftentimes the question does not include significant and important facts and timelines that if known could significantly change the reply or make such reply unsuitable. Mr. Dial strongly advises the questioner to confer with an attorney in their state in order to ensure proper advice is received.
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