question about getting custody of a child?

Your husband can go to Court and file a petition for custody and ask to have his name added to the birth certificate (this has to be ordered by a Judge). Once your husband has a court order for custody you should be able to add her to your insurance since you are married. Adopting is a little more tricky and you probably do need a lawyer for that.

Have you called the insurance company to ask what they would want to have her added to the insurance. If the child is a dependent anyway it may not be that much in a step-parent situation. You might just have to tell the insurance company as much.

As far as adoption goes, it should not be that hard in a step-parent situation. depending on the state that you are in. The main reason you might want to consider adoption is if your husband somehow died. Where would the daughter end up? If the husband wanterd her to be with you, that might be hard to do without adoption.

Mutt gave you the right answer. You need to consult with an attorney to find out exactly what needs to be done and done properly from the get go. There's no short way around it unfortunately.

Get a lawyer to draw up the papers and get it finalized in court.