Your legal rights amount to virtually nil, zip, zero.. If your hubby dies, the bio mum can take custody of the child and you may never see her again. It would be very difficult to pursue visitation to a step child.
The only way you can adopt her is if the bio mother agrees and signs away her rights. She may be willing to do that.. but you have to ask.. Well, your hubby needs to ask. However, I personally would not do this until you have been married for a few years. Otherwise, if you adopt and then divorce after a year, you will end up paying child support for the next 15 years as it would be unlikely you would get custody.
You are however considered a guardian and can sign for her.. and in almost every way, act as her mom. If you are worried, get your fiance to get a paper drawn up to say you are the a legal guardian. This is very wise when the child is so young and can not speak properly for herself.
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SMILE - Start Making It Livable for Everyone
Divorce is a process over which children have no control. Children should not be its victims.
When parents are under stress, it is harder to be in touch with their children's pain and anguish.
It takes time, effort, and planning on the part of the parents to be able to provide for the children's needs.
In the crisis of divorce, parents may put their children on hold while they attend to adult problems first.
Sometimes separating/divorced parents find that their roles and expectations are undefined and cloudy.
If handled properly, divorce need not be devastating for children.